[PATCH v7 1/1] selftests/mm/uffd: Refactor non-composite global vars into struct - Linux-kselftest-mirror

17 Aug 2025

Refactor macros and non-composite global variable definitions into a
struct that is defined at the start of a test and is passed around
instead of relying on global vars.
Signed-off-by: Ujwal Kundur ujwal.kundur@gmail.com
Acked-by: Peter Xu peterx@redhat.com
---
Previous versions and discussion at:
https://lore.kernel.org/all/20250702152057.4067-1-ujwal.kundur@gmail.com/
Changes since v6:
 - rebased on 6.17-rc1 changes (cd79a1d9b08a)
   - removes unused args and adds the __unused attribute; since change
     is cosmetic-only, carry forward Acked-by tag
 - verified output remains unchanged using virtme-ng
 Changes since v5:
 - ensure uffd_global_test_opts_t instances are initialized
 - verified output remains unchanged using virtme-ng
 Changes since v4:
 - define gopts as global within uffd-stress.c to retain existing
   sigalrm handler logic
 Changes since v3:
 - more formatting fixes
 Changes since v2:
 - redo patch on mm-new branch
 Changes since v1:
 - indentation fixes
 - squash into single patch to assist bisections
tools/testing/selftests/mm/uffd-common.c     | 275 ++++-----
 tools/testing/selftests/mm/uffd-common.h     |  78 +--
 tools/testing/selftests/mm/uffd-stress.c     | 228 ++++----
 tools/testing/selftests/mm/uffd-unit-tests.c | 561 ++++++++++---------
 tools/testing/selftests/mm/uffd-wp-mremap.c  |  23 +-
 5 files changed, 623 insertions(+), 542 deletions(-)

diff --git a/tools/testing/selftests/mm/uffd-common.c b/tools/testing/selftests/mm/uffd-common.c
index e309ec886fa7..f4e9a5f43e24 100644
--- a/tools/testing/selftests/mm/uffd-common.c
+++ b/tools/testing/selftests/mm/uffd-common.c
@@ -7,18 +7,30 @@
#include "uffd-common.h"
-#define BASE_PMD_ADDR ((void *)(1UL << 30))
-
-volatile bool test_uffdio_copy_eexist = true;
-unsigned long nr_parallel, nr_pages, nr_pages_per_cpu, page_size;
-char *area_src, *area_src_alias, *area_dst, *area_dst_alias, *area_remap;
-int uffd = -1, uffd_flags, finished, *pipefd, test_type;
-bool map_shared;
-bool test_uffdio_wp = true;
-unsigned long long *count_verify;
 uffd_test_ops_t *uffd_test_ops;
 uffd_test_case_ops_t *uffd_test_case_ops;
-atomic_bool ready_for_fork;
+
+#define BASE_PMD_ADDR ((void *)(1UL << 30))
+
+/* pthread_mutex_t starts at page offset 0 */
+pthread_mutex_t *area_mutex(char *area, unsigned long nr, uffd_global_test_opts_t *gopts)
+{
+	return (pthread_mutex_t *) (area + nr * gopts->page_size);
+}
+
+/*
+ * count is placed in the page after pthread_mutex_t naturally aligned
+ * to avoid non alignment faults on non-x86 archs.
+ */
+volatile unsigned long long *area_count(
+		char *area, unsigned long nr,
+		uffd_global_test_opts_t *gopts)
+{
+	return (volatile unsigned long long *)
+	       ((unsigned long)(area + nr * gopts->page_size +
+	       sizeof(pthread_mutex_t) + sizeof(unsigned long long) - 1) &
+	       ~(unsigned long)(sizeof(unsigned long long) - 1));
+}
static int uffd_mem_fd_create(off_t mem_size, bool hugetlb)
 {
@@ -40,15 +52,16 @@ static int uffd_mem_fd_create(off_t mem_size, bool hugetlb)
    return mem_fd;
 }
-static void anon_release_pages(char *rel_area)
+static void anon_release_pages(uffd_global_test_opts_t *gopts, char *rel_area)
 {
-	if (madvise(rel_area, nr_pages * page_size, MADV_DONTNEED))
+	if (madvise(rel_area, gopts->nr_pages * gopts->page_size, MADV_DONTNEED))
    	err("madvise(MADV_DONTNEED) failed");
 }
-static int anon_allocate_area(void **alloc_area, bool __unused is_src)
+static int anon_allocate_area(uffd_global_test_opts_t *gopts, void **alloc_area,
+			      bool __unused is_src)
 {
-	*alloc_area = mmap(NULL, nr_pages * page_size, PROT_READ | PROT_WRITE,
+	*alloc_area = mmap(NULL, gopts->nr_pages * gopts->page_size, PROT_READ | PROT_WRITE,
    		   MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
    if (*alloc_area == MAP_FAILED) {
    	*alloc_area = NULL;
@@ -57,32 +70,32 @@ static int anon_allocate_area(void **alloc_area, bool __unused is_src)
    return 0;
 }
-static void noop_alias_mapping(__u64 __unused *start, size_t __unused len,
-			       unsigned long __unused offset)
+static void noop_alias_mapping(uffd_global_test_opts_t *gopts, __u64 __unused *start,
+			       size_t __unused len, unsigned long __unused offset)
 {
 }
-static void hugetlb_release_pages(char *rel_area)
+static void hugetlb_release_pages(uffd_global_test_opts_t *gopts, char *rel_area)
 {
-	if (!map_shared) {
-		if (madvise(rel_area, nr_pages * page_size, MADV_DONTNEED))
+	if (!gopts->map_shared) {
+		if (madvise(rel_area, gopts->nr_pages * gopts->page_size, MADV_DONTNEED))
    		err("madvise(MADV_DONTNEED) failed");
    } else {
-		if (madvise(rel_area, nr_pages * page_size, MADV_REMOVE))
+		if (madvise(rel_area, gopts->nr_pages * gopts->page_size, MADV_REMOVE))
    		err("madvise(MADV_REMOVE) failed");
    }
 }
-static int hugetlb_allocate_area(void **alloc_area, bool is_src)
+static int hugetlb_allocate_area(uffd_global_test_opts_t *gopts, void **alloc_area, bool is_src)
 {
-	off_t size = nr_pages * page_size;
+	off_t size = gopts->nr_pages * gopts->page_size;
    off_t offset = is_src ? 0 : size;
    void *area_alias = NULL;
    char **alloc_area_alias;
    int mem_fd = uffd_mem_fd_create(size * 2, true);
*alloc_area = mmap(NULL, size, PROT_READ | PROT_WRITE,
-			   (map_shared ? MAP_SHARED : MAP_PRIVATE) |
+			   (gopts->map_shared ? MAP_SHARED : MAP_PRIVATE) |
    		   (is_src ? 0 : MAP_NORESERVE),
    		   mem_fd, offset);
    if (*alloc_area == MAP_FAILED) {
@@ -90,7 +103,7 @@ static int hugetlb_allocate_area(void **alloc_area, bool is_src)
    	return -errno;
    }
-	if (map_shared) {
+	if (gopts->map_shared) {
    	area_alias = mmap(NULL, size, PROT_READ | PROT_WRITE,
    			  MAP_SHARED, mem_fd, offset);
    	if (area_alias == MAP_FAILED)
@@ -98,9 +111,9 @@ static int hugetlb_allocate_area(void **alloc_area, bool is_src)
    }
if (is_src) {
-		alloc_area_alias = &area_src_alias;
+		alloc_area_alias = &gopts->area_src_alias;
    } else {
-		alloc_area_alias = &area_dst_alias;
+		alloc_area_alias = &gopts->area_dst_alias;
    }
    if (area_alias)
    	*alloc_area_alias = area_alias;
@@ -109,24 +122,25 @@ static int hugetlb_allocate_area(void **alloc_area, bool is_src)
    return 0;
 }
-static void hugetlb_alias_mapping(__u64 *start, size_t __unused len, unsigned long offset)
+static void hugetlb_alias_mapping(uffd_global_test_opts_t *gopts, __u64 *start,
+				  size_t __unused len, unsigned long offset)
 {
-	if (!map_shared)
+	if (!gopts->map_shared)
    	return;
-	*start = (unsigned long) area_dst_alias + offset;
+	*start = (unsigned long) gopts->area_dst_alias + offset;
 }
-static void shmem_release_pages(char *rel_area)
+static void shmem_release_pages(uffd_global_test_opts_t *gopts, char *rel_area)
 {
-	if (madvise(rel_area, nr_pages * page_size, MADV_REMOVE))
+	if (madvise(rel_area, gopts->nr_pages * gopts->page_size, MADV_REMOVE))
    	err("madvise(MADV_REMOVE) failed");
 }
-static int shmem_allocate_area(void **alloc_area, bool is_src)
+static int shmem_allocate_area(uffd_global_test_opts_t *gopts, void **alloc_area, bool is_src)
 {
    void *area_alias = NULL;
-	size_t bytes = nr_pages * page_size, hpage_size = read_pmd_pagesize();
+	size_t bytes = gopts->nr_pages * gopts->page_size, hpage_size = read_pmd_pagesize();
    unsigned long offset = is_src ? 0 : bytes;
    char *p = NULL, *p_alias = NULL;
    int mem_fd = uffd_mem_fd_create(bytes * 2, false);
@@ -160,22 +174,24 @@ static int shmem_allocate_area(void **alloc_area, bool is_src)
    	err("mmap of anonymous memory failed at %p", p_alias);
if (is_src)
-		area_src_alias = area_alias;
+		gopts->area_src_alias = area_alias;
    else
-		area_dst_alias = area_alias;
+		gopts->area_dst_alias = area_alias;
close(mem_fd);
    return 0;
 }
-static void shmem_alias_mapping(__u64 *start, size_t __unused len, unsigned long offset)
+static void shmem_alias_mapping(uffd_global_test_opts_t *gopts, __u64 *start,
+				size_t __unused len, unsigned long offset)
 {
-	*start = (unsigned long)area_dst_alias + offset;
+	*start = (unsigned long)gopts->area_dst_alias + offset;
 }
-static void shmem_check_pmd_mapping(void __unused *p, int expect_nr_hpages)
+static void shmem_check_pmd_mapping(uffd_global_test_opts_t *gopts, void __unused *p,
+				    int expect_nr_hpages)
 {
-	if (!check_huge_shmem(area_dst_alias, expect_nr_hpages,
+	if (!check_huge_shmem(gopts->area_dst_alias, expect_nr_hpages,
    		      read_pmd_pagesize()))
    	err("Did not find expected %d number of hugepages",
    	    expect_nr_hpages);
@@ -235,18 +251,18 @@ void uffd_stats_report(struct uffd_args *args, int n_cpus)
    printf("\n");
 }
-int userfaultfd_open(uint64_t *features)
+int userfaultfd_open(uffd_global_test_opts_t *gopts, uint64_t *features)
 {
    struct uffdio_api uffdio_api;
-	uffd = uffd_open(UFFD_FLAGS);
-	if (uffd < 0)
+	gopts->uffd = uffd_open(UFFD_FLAGS);
+	if (gopts->uffd < 0)
    	return -1;
-	uffd_flags = fcntl(uffd, F_GETFD, NULL);
+	gopts->uffd_flags = fcntl(gopts->uffd, F_GETFD, NULL);
uffdio_api.api = UFFD_API;
    uffdio_api.features = *features;
-	if (ioctl(uffd, UFFDIO_API, &uffdio_api))
+	if (ioctl(gopts->uffd, UFFDIO_API, &uffdio_api))
    	/* Probably lack of CAP_PTRACE? */
    	return -1;
    if (uffdio_api.api != UFFD_API)
@@ -256,59 +272,63 @@ int userfaultfd_open(uint64_t *features)
    return 0;
 }
-static inline void munmap_area(void **area)
+static inline void munmap_area(uffd_global_test_opts_t *gopts, void **area)
 {
    if (*area)
-		if (munmap(*area, nr_pages * page_size))
+		if (munmap(*area, gopts->nr_pages * gopts->page_size))
    		err("munmap");
*area = NULL;
 }
-void uffd_test_ctx_clear(void)
+void uffd_test_ctx_clear(uffd_global_test_opts_t *gopts)
 {
    size_t i;
-	if (pipefd) {
-		for (i = 0; i < nr_parallel * 2; ++i) {
-			if (close(pipefd[i]))
+	if (gopts->pipefd) {
+		for (i = 0; i < gopts->nr_parallel * 2; ++i) {
+			if (close(gopts->pipefd[i]))
    			err("close pipefd");
    	}
-		free(pipefd);
-		pipefd = NULL;
+		free(gopts->pipefd);
+		gopts->pipefd = NULL;
    }
-	if (count_verify) {
-		free(count_verify);
-		count_verify = NULL;
+	if (gopts->count_verify) {
+		free(gopts->count_verify);
+		gopts->count_verify = NULL;
    }
-	if (uffd != -1) {
-		if (close(uffd))
+	if (gopts->uffd != -1) {
+		if (close(gopts->uffd))
    		err("close uffd");
-		uffd = -1;
+		gopts->uffd = -1;
    }
-	munmap_area((void **)&area_src);
-	munmap_area((void **)&area_src_alias);
-	munmap_area((void **)&area_dst);
-	munmap_area((void **)&area_dst_alias);
-	munmap_area((void **)&area_remap);
+	munmap_area(gopts, (void **)&gopts->area_src);
+	munmap_area(gopts, (void **)&gopts->area_src_alias);
+	munmap_area(gopts, (void **)&gopts->area_dst);
+	munmap_area(gopts, (void **)&gopts->area_dst_alias);
+	munmap_area(gopts, (void **)&gopts->area_remap);
 }
-int uffd_test_ctx_init(uint64_t features, const char **errmsg)
+int uffd_test_ctx_init(uffd_global_test_opts_t *gopts, uint64_t features, const char **errmsg)
 {
    unsigned long nr, cpu;
    int ret;
+	gopts->area_src_alias = NULL;
+	gopts->area_dst_alias = NULL;
+	gopts->area_remap = NULL;
+
    if (uffd_test_case_ops && uffd_test_case_ops->pre_alloc) {
-		ret = uffd_test_case_ops->pre_alloc(errmsg);
+		ret = uffd_test_case_ops->pre_alloc(gopts, errmsg);
    	if (ret)
    		return ret;
    }
-	ret = uffd_test_ops->allocate_area((void **)&area_src, true);
-	ret |= uffd_test_ops->allocate_area((void **)&area_dst, false);
+	ret = uffd_test_ops->allocate_area(gopts, (void **) &gopts->area_src, true);
+	ret |= uffd_test_ops->allocate_area(gopts, (void **) &gopts->area_dst, false);
    if (ret) {
    	if (errmsg)
    		*errmsg = "memory allocation failed";
@@ -316,26 +336,26 @@ int uffd_test_ctx_init(uint64_t features, const char **errmsg)
    }
if (uffd_test_case_ops && uffd_test_case_ops->post_alloc) {
-		ret = uffd_test_case_ops->post_alloc(errmsg);
+		ret = uffd_test_case_ops->post_alloc(gopts, errmsg);
    	if (ret)
    		return ret;
    }
-	ret = userfaultfd_open(&features);
+	ret = userfaultfd_open(gopts, &features);
    if (ret) {
    	if (errmsg)
    		*errmsg = "possible lack of privilege";
    	return ret;
    }
-	count_verify = malloc(nr_pages * sizeof(unsigned long long));
-	if (!count_verify)
+	gopts->count_verify = malloc(gopts->nr_pages * sizeof(unsigned long long));
+	if (!gopts->count_verify)
    	err("count_verify");
-	for (nr = 0; nr < nr_pages; nr++) {
-		*area_mutex(area_src, nr) =
+	for (nr = 0; nr < gopts->nr_pages; nr++) {
+		*area_mutex(gopts->area_src, nr, gopts) =
    		(pthread_mutex_t)PTHREAD_MUTEX_INITIALIZER;
-		count_verify[nr] = *area_count(area_src, nr) = 1;
+		gopts->count_verify[nr] = *area_count(gopts->area_src, nr, gopts) = 1;
    	/*
    	 * In the transition between 255 to 256, powerpc will
    	 * read out of order in my_bcmp and see both bytes as
@@ -343,7 +363,7 @@ int uffd_test_ctx_init(uint64_t features, const char **errmsg)
    	 * after the count, to avoid my_bcmp to trigger false
    	 * positives.
    	 */
-		*(area_count(area_src, nr) + 1) = 1;
+		*(area_count(gopts->area_src, nr, gopts) + 1) = 1;
    }
/*
@@ -364,13 +384,13 @@ int uffd_test_ctx_init(uint64_t features, const char **errmsg)
     * proactively split the thp and drop any accidentally initialized
     * pages within area_dst.
     */
-	uffd_test_ops->release_pages(area_dst);
+	uffd_test_ops->release_pages(gopts, gopts->area_dst);
-	pipefd = malloc(sizeof(int) * nr_parallel * 2);
-	if (!pipefd)
+	gopts->pipefd = malloc(sizeof(int) * gopts->nr_parallel * 2);
+	if (!gopts->pipefd)
    	err("pipefd");
-	for (cpu = 0; cpu < nr_parallel; cpu++)
-		if (pipe2(&pipefd[cpu * 2], O_CLOEXEC | O_NONBLOCK))
+	for (cpu = 0; cpu < gopts->nr_parallel; cpu++)
+		if (pipe2(&gopts->pipefd[cpu * 2], O_CLOEXEC | O_NONBLOCK))
    		err("pipe");
return 0;
@@ -417,9 +437,9 @@ static void continue_range(int ufd, __u64 start, __u64 len, bool wp)
    	    ret, (int64_t) req.mapped);
 }
-int uffd_read_msg(struct uffd_msg *msg)
+int uffd_read_msg(uffd_global_test_opts_t *gopts, struct uffd_msg *msg)
 {
-	int ret = read(uffd, msg, sizeof(*msg));
+	int ret = read(gopts->uffd, msg, sizeof(*msg));
if (ret != sizeof(*msg)) {
    	if (ret < 0) {
@@ -434,7 +454,8 @@ int uffd_read_msg(struct uffd_msg *msg)
    return 0;
 }
-void uffd_handle_page_fault(struct uffd_msg *msg, struct uffd_args *args)
+void uffd_handle_page_fault(uffd_global_test_opts_t *gopts, struct uffd_msg *msg,
+			    struct uffd_args *args)
 {
    unsigned long offset;
@@ -443,7 +464,7 @@ void uffd_handle_page_fault(struct uffd_msg *msg, struct uffd_args *args)
if (msg->arg.pagefault.flags & UFFD_PAGEFAULT_FLAG_WP) {
    	/* Write protect page faults */
-		wp_range(uffd, msg->arg.pagefault.address, page_size, false);
+		wp_range(gopts->uffd, msg->arg.pagefault.address, gopts->page_size, false);
    	args->wp_faults++;
    } else if (msg->arg.pagefault.flags & UFFD_PAGEFAULT_FLAG_MINOR) {
    	uint8_t *area;
@@ -461,12 +482,12 @@ void uffd_handle_page_fault(struct uffd_msg *msg, struct uffd_args *args)
    	 * (UFFD-registered).
    	 */
-		area = (uint8_t *)(area_dst +
-				   ((char *)msg->arg.pagefault.address -
-				    area_dst_alias));
-		for (b = 0; b < page_size; ++b)
+		area = (uint8_t *)(gopts->area_dst +
+		       ((char *)msg->arg.pagefault.address -
+		       gopts->area_dst_alias));
+		for (b = 0; b < gopts->page_size; ++b)
    		area[b] = ~area[b];
-		continue_range(uffd, msg->arg.pagefault.address, page_size,
+		continue_range(gopts->uffd, msg->arg.pagefault.address, gopts->page_size,
    		       args->apply_wp);
    	args->minor_faults++;
    } else {
@@ -494,10 +515,10 @@ void uffd_handle_page_fault(struct uffd_msg *msg, struct uffd_args *args)
    	if (msg->arg.pagefault.flags & UFFD_PAGEFAULT_FLAG_WRITE)
    		err("unexpected write fault");
-		offset = (char *)(unsigned long)msg->arg.pagefault.address - area_dst;
-		offset &= ~(page_size-1);
+		offset = (char *)(unsigned long)msg->arg.pagefault.address - gopts->area_dst;
+		offset &= ~(gopts->page_size-1);
-		if (copy_page(uffd, offset, args->apply_wp))
+		if (copy_page(gopts, offset, args->apply_wp))
    		args->missing_faults++;
    }
 }
@@ -505,6 +526,7 @@ void uffd_handle_page_fault(struct uffd_msg *msg, struct uffd_args *args)
 void *uffd_poll_thread(void *arg)
 {
    struct uffd_args *args = (struct uffd_args *)arg;
+	uffd_global_test_opts_t *gopts = args->gopts;
    unsigned long cpu = args->cpu;
    struct pollfd pollfd[2];
    struct uffd_msg msg;
@@ -515,12 +537,12 @@ void *uffd_poll_thread(void *arg)
    if (!args->handle_fault)
    	args->handle_fault = uffd_handle_page_fault;
-	pollfd[0].fd = uffd;
+	pollfd[0].fd = gopts->uffd;
    pollfd[0].events = POLLIN;
-	pollfd[1].fd = pipefd[cpu*2];
+	pollfd[1].fd = gopts->pipefd[cpu*2];
    pollfd[1].events = POLLIN;
-	ready_for_fork = true;
+	gopts->ready_for_fork = true;
for (;;) {
    	ret = poll(pollfd, 2, -1);
@@ -538,30 +560,30 @@ void *uffd_poll_thread(void *arg)
    	}
    	if (!(pollfd[0].revents & POLLIN))
    		err("pollfd[0].revents %d", pollfd[0].revents);
-		if (uffd_read_msg(&msg))
+		if (uffd_read_msg(gopts, &msg))
    		continue;
    	switch (msg.event) {
    	default:
    		err("unexpected msg event %u\n", msg.event);
    		break;
    	case UFFD_EVENT_PAGEFAULT:
-			args->handle_fault(&msg, args);
+			args->handle_fault(gopts, &msg, args);
    		break;
    	case UFFD_EVENT_FORK:
-			close(uffd);
-			uffd = msg.arg.fork.ufd;
-			pollfd[0].fd = uffd;
+			close(gopts->uffd);
+			gopts->uffd = msg.arg.fork.ufd;
+			pollfd[0].fd = gopts->uffd;
    		break;
    	case UFFD_EVENT_REMOVE:
    		uffd_reg.range.start = msg.arg.remove.start;
    		uffd_reg.range.len = msg.arg.remove.end -
    			msg.arg.remove.start;
-			if (ioctl(uffd, UFFDIO_UNREGISTER, &uffd_reg.range))
+			if (ioctl(gopts->uffd, UFFDIO_UNREGISTER, &uffd_reg.range))
    			err("remove failure");
    		break;
    	case UFFD_EVENT_REMAP:
-			area_remap = area_dst;  /* save for later unmap */
-			area_dst = (char *)(unsigned long)msg.arg.remap.to;
+			gopts->area_remap = gopts->area_dst;  /* save for later unmap */
+			gopts->area_dst = (char *)(unsigned long)msg.arg.remap.to;
    		break;
    	}
    }
@@ -569,17 +591,18 @@ void *uffd_poll_thread(void *arg)
    return NULL;
 }
-static void retry_copy_page(int ufd, struct uffdio_copy *uffdio_copy,
+static void retry_copy_page(uffd_global_test_opts_t *gopts, struct uffdio_copy *uffdio_copy,
    		    unsigned long offset)
 {
-	uffd_test_ops->alias_mapping(&uffdio_copy->dst,
+	uffd_test_ops->alias_mapping(gopts,
+				     &uffdio_copy->dst,
    			     uffdio_copy->len,
    			     offset);
-	if (ioctl(ufd, UFFDIO_COPY, uffdio_copy)) {
+	if (ioctl(gopts->uffd, UFFDIO_COPY, uffdio_copy)) {
    	/* real retval in ufdio_copy.copy */
    	if (uffdio_copy->copy != -EEXIST)
    		err("UFFDIO_COPY retry error: %"PRId64,
-			    (int64_t)uffdio_copy->copy);
+			(int64_t)uffdio_copy->copy);
    } else {
    	err("UFFDIO_COPY retry unexpected: %"PRId64,
    	    (int64_t)uffdio_copy->copy);
@@ -598,60 +621,60 @@ static void wake_range(int ufd, unsigned long addr, unsigned long len)
    		addr), exit(1);
 }
-int __copy_page(int ufd, unsigned long offset, bool retry, bool wp)
+int __copy_page(uffd_global_test_opts_t *gopts, unsigned long offset, bool retry, bool wp)
 {
    struct uffdio_copy uffdio_copy;
-	if (offset >= nr_pages * page_size)
+	if (offset >= gopts->nr_pages * gopts->page_size)
    	err("unexpected offset %lu\n", offset);
-	uffdio_copy.dst = (unsigned long) area_dst + offset;
-	uffdio_copy.src = (unsigned long) area_src + offset;
-	uffdio_copy.len = page_size;
+	uffdio_copy.dst = (unsigned long) gopts->area_dst + offset;
+	uffdio_copy.src = (unsigned long) gopts->area_src + offset;
+	uffdio_copy.len = gopts->page_size;
    if (wp)
    	uffdio_copy.mode = UFFDIO_COPY_MODE_WP;
    else
    	uffdio_copy.mode = 0;
    uffdio_copy.copy = 0;
-	if (ioctl(ufd, UFFDIO_COPY, &uffdio_copy)) {
+	if (ioctl(gopts->uffd, UFFDIO_COPY, &uffdio_copy)) {
    	/* real retval in ufdio_copy.copy */
    	if (uffdio_copy.copy != -EEXIST)
    		err("UFFDIO_COPY error: %"PRId64,
    		    (int64_t)uffdio_copy.copy);
-		wake_range(ufd, uffdio_copy.dst, page_size);
-	} else if (uffdio_copy.copy != page_size) {
+		wake_range(gopts->uffd, uffdio_copy.dst, gopts->page_size);
+	} else if (uffdio_copy.copy != gopts->page_size) {
    	err("UFFDIO_COPY error: %"PRId64, (int64_t)uffdio_copy.copy);
    } else {
-		if (test_uffdio_copy_eexist && retry) {
-			test_uffdio_copy_eexist = false;
-			retry_copy_page(ufd, &uffdio_copy, offset);
+		if (gopts->test_uffdio_copy_eexist && retry) {
+			gopts->test_uffdio_copy_eexist = false;
+			retry_copy_page(gopts, &uffdio_copy, offset);
    	}
    	return 1;
    }
    return 0;
 }
-int copy_page(int ufd, unsigned long offset, bool wp)
+int copy_page(uffd_global_test_opts_t *gopts, unsigned long offset, bool wp)
 {
-	return __copy_page(ufd, offset, false, wp);
+	return __copy_page(gopts, offset, false, wp);
 }
-int move_page(int ufd, unsigned long offset, unsigned long len)
+int move_page(uffd_global_test_opts_t *gopts, unsigned long offset, unsigned long len)
 {
    struct uffdio_move uffdio_move;
-	if (offset + len > nr_pages * page_size)
+	if (offset + len > gopts->nr_pages * gopts->page_size)
    	err("unexpected offset %lu and length %lu\n", offset, len);
-	uffdio_move.dst = (unsigned long) area_dst + offset;
-	uffdio_move.src = (unsigned long) area_src + offset;
+	uffdio_move.dst = (unsigned long) gopts->area_dst + offset;
+	uffdio_move.src = (unsigned long) gopts->area_src + offset;
    uffdio_move.len = len;
    uffdio_move.mode = UFFDIO_MOVE_MODE_ALLOW_SRC_HOLES;
    uffdio_move.move = 0;
-	if (ioctl(ufd, UFFDIO_MOVE, &uffdio_move)) {
+	if (ioctl(gopts->uffd, UFFDIO_MOVE, &uffdio_move)) {
    	/* real retval in uffdio_move.move */
    	if (uffdio_move.move != -EEXIST)
    		err("UFFDIO_MOVE error: %"PRId64,
    		    (int64_t)uffdio_move.move);
-		wake_range(ufd, uffdio_move.dst, len);
+		wake_range(gopts->uffd, uffdio_move.dst, len);
    } else if (uffdio_move.move != len) {
    	err("UFFDIO_MOVE error: %"PRId64, (int64_t)uffdio_move.move);
    } else
diff --git a/tools/testing/selftests/mm/uffd-common.h b/tools/testing/selftests/mm/uffd-common.h
index 2e7066d69103..37d3ca55905f 100644
--- a/tools/testing/selftests/mm/uffd-common.h
+++ b/tools/testing/selftests/mm/uffd-common.h
@@ -56,20 +56,17 @@
#define err(fmt, ...) errexit(1, fmt, ##__VA_ARGS__)
-/* pthread_mutex_t starts at page offset 0 */
-#define area_mutex(___area, ___nr)					\
-	((pthread_mutex_t *) ((___area) + (___nr)*page_size))
-/*
- * count is placed in the page after pthread_mutex_t naturally aligned
- * to avoid non alignment faults on non-x86 archs.
- */
-#define area_count(___area, ___nr)					\
-	((volatile unsigned long long *) ((unsigned long)		\
-				 ((___area) + (___nr)*page_size +	\
-				  sizeof(pthread_mutex_t) +		\
-				  sizeof(unsigned long long) - 1) &	\
-				 ~(unsigned long)(sizeof(unsigned long long) \
-						  -  1)))
+struct uffd_global_test_opts {
+	unsigned long nr_parallel, nr_pages, nr_pages_per_cpu, page_size;
+	char *area_src, *area_src_alias, *area_dst, *area_dst_alias, *area_remap;
+	int uffd, uffd_flags, finished, *pipefd, test_type;
+	bool map_shared;
+	bool test_uffdio_wp;
+	unsigned long long *count_verify;
+	volatile bool test_uffdio_copy_eexist;
+	atomic_bool ready_for_fork;
+};
+typedef struct uffd_global_test_opts uffd_global_test_opts_t;
/* Userfaultfd test statistics */
 struct uffd_args {
@@ -79,50 +76,55 @@ struct uffd_args {
    unsigned long missing_faults;
    unsigned long wp_faults;
    unsigned long minor_faults;
+	struct uffd_global_test_opts *gopts;
/* A custom fault handler; defaults to uffd_handle_page_fault. */
-	void (*handle_fault)(struct uffd_msg *msg, struct uffd_args *args);
+	void (*handle_fault)(struct uffd_global_test_opts *gopts,
+			     struct uffd_msg *msg,
+			     struct uffd_args *args);
 };
struct uffd_test_ops {
-	int (*allocate_area)(void **alloc_area, bool is_src);
-	void (*release_pages)(char *rel_area);
-	void (*alias_mapping)(__u64 *start, size_t len, unsigned long offset);
-	void (*check_pmd_mapping)(void *p, int expect_nr_hpages);
+	int (*allocate_area)(uffd_global_test_opts_t *gopts, void **alloc_area, bool is_src);
+	void (*release_pages)(uffd_global_test_opts_t *gopts, char *rel_area);
+	void (*alias_mapping)(uffd_global_test_opts_t *gopts,
+			      __u64 *start,
+			      size_t len,
+			      unsigned long offset);
+	void (*check_pmd_mapping)(uffd_global_test_opts_t *gopts, void *p, int expect_nr_hpages);
 };
 typedef struct uffd_test_ops uffd_test_ops_t;
struct uffd_test_case_ops {
-	int (*pre_alloc)(const char **errmsg);
-	int (*post_alloc)(const char **errmsg);
+	int (*pre_alloc)(uffd_global_test_opts_t *gopts, const char **errmsg);
+	int (*post_alloc)(uffd_global_test_opts_t *gopts, const char **errmsg);
 };
 typedef struct uffd_test_case_ops uffd_test_case_ops_t;
-extern unsigned long nr_parallel, nr_pages, nr_pages_per_cpu, page_size;
-extern char *area_src, *area_src_alias, *area_dst, *area_dst_alias, *area_remap;
-extern int uffd, uffd_flags, finished, *pipefd, test_type;
-extern bool map_shared;
-extern bool test_uffdio_wp;
-extern unsigned long long *count_verify;
-extern volatile bool test_uffdio_copy_eexist;
-extern atomic_bool ready_for_fork;
-
+extern uffd_global_test_opts_t *uffd_gtest_opts;
 extern uffd_test_ops_t anon_uffd_test_ops;
 extern uffd_test_ops_t shmem_uffd_test_ops;
 extern uffd_test_ops_t hugetlb_uffd_test_ops;
 extern uffd_test_ops_t *uffd_test_ops;
 extern uffd_test_case_ops_t *uffd_test_case_ops;
+pthread_mutex_t *area_mutex(char *area, unsigned long nr, uffd_global_test_opts_t *gopts);
+volatile unsigned long long *area_count(char *area,
+					unsigned long nr,
+					uffd_global_test_opts_t *gopts);
+
 void uffd_stats_report(struct uffd_args *args, int n_cpus);
-int uffd_test_ctx_init(uint64_t features, const char **errmsg);
-void uffd_test_ctx_clear(void);
-int userfaultfd_open(uint64_t *features);
-int uffd_read_msg(struct uffd_msg *msg);
+int uffd_test_ctx_init(uffd_global_test_opts_t *gopts, uint64_t features, const char **errmsg);
+void uffd_test_ctx_clear(uffd_global_test_opts_t *gopts);
+int userfaultfd_open(uffd_global_test_opts_t *gopts, uint64_t *features);
+int uffd_read_msg(uffd_global_test_opts_t *gopts, struct uffd_msg *msg);
 void wp_range(int ufd, __u64 start, __u64 len, bool wp);
-void uffd_handle_page_fault(struct uffd_msg *msg, struct uffd_args *args);
-int __copy_page(int ufd, unsigned long offset, bool retry, bool wp);
-int copy_page(int ufd, unsigned long offset, bool wp);
-int move_page(int ufd, unsigned long offset, unsigned long len);
+void uffd_handle_page_fault(uffd_global_test_opts_t *gopts,
+			    struct uffd_msg *msg,
+			    struct uffd_args *args);
+int __copy_page(uffd_global_test_opts_t *gopts, unsigned long offset, bool retry, bool wp);
+int copy_page(uffd_global_test_opts_t *gopts, unsigned long offset, bool wp);
+int move_page(uffd_global_test_opts_t *gopts, unsigned long offset, unsigned long len);
 void *uffd_poll_thread(void *arg);
int uffd_open_dev(unsigned int flags);
diff --git a/tools/testing/selftests/mm/uffd-stress.c b/tools/testing/selftests/mm/uffd-stress.c
index 24aac0ae96c6..9b216e842bbb 100644
--- a/tools/testing/selftests/mm/uffd-stress.c
+++ b/tools/testing/selftests/mm/uffd-stress.c
@@ -44,6 +44,12 @@ uint64_t features;
 #define BOUNCE_VERIFY		(1<<2)
 #define BOUNCE_POLL		(1<<3)
 static int bounces;
+/* defined globally for this particular test as the sigalrm handler
+ * depends on test_uffdio_*_eexist.
+ * XXX: define gopts in main() when we figure out a way to deal with
+ * test_uffdio_*_eexist.
+ */
+static uffd_global_test_opts_t *gopts;
/* exercise the test_uffdio_*_eexist every ALARM_INTERVAL_SECS */
 #define ALARM_INTERVAL_SECS 10
@@ -76,54 +82,58 @@ static void usage(void)
    exit(1);
 }
-static void uffd_stats_reset(struct uffd_args *args, unsigned long n_cpus)
+static void uffd_stats_reset(uffd_global_test_opts_t *gopts, struct uffd_args *args,
+			     unsigned long n_cpus)
 {
    int i;
for (i = 0; i < n_cpus; i++) {
    	args[i].cpu = i;
-		args[i].apply_wp = test_uffdio_wp;
+		args[i].apply_wp = gopts->test_uffdio_wp;
    	args[i].missing_faults = 0;
    	args[i].wp_faults = 0;
    	args[i].minor_faults = 0;
+		args[i].gopts = gopts;
    }
 }
static void *locking_thread(void *arg)
 {
-	unsigned long cpu = (unsigned long) arg;
+	struct uffd_args *args = (struct uffd_args *) arg;
+	uffd_global_test_opts_t *gopts = args->gopts;
+	unsigned long cpu = (unsigned long) args->cpu;
    unsigned long page_nr;
    unsigned long long count;
if (!(bounces & BOUNCE_RANDOM)) {
    	page_nr = -bounces;
    	if (!(bounces & BOUNCE_RACINGFAULTS))
-			page_nr += cpu * nr_pages_per_cpu;
+			page_nr += cpu * gopts->nr_pages_per_cpu;
    }
-	while (!finished) {
+	while (!gopts->finished) {
    	if (bounces & BOUNCE_RANDOM) {
    		if (getrandom(&page_nr, sizeof(page_nr), 0) != sizeof(page_nr))
    			err("getrandom failed");
    	} else
    		page_nr += 1;
-		page_nr %= nr_pages;
-		pthread_mutex_lock(area_mutex(area_dst, page_nr));
-		count = *area_count(area_dst, page_nr);
-		if (count != count_verify[page_nr])
+		page_nr %= gopts->nr_pages;
+		pthread_mutex_lock(area_mutex(gopts->area_dst, page_nr, gopts));
+		count = *area_count(gopts->area_dst, page_nr, gopts);
+		if (count != gopts->count_verify[page_nr])
    		err("page_nr %lu memory corruption %llu %llu",
-			    page_nr, count, count_verify[page_nr]);
+			    page_nr, count, gopts->count_verify[page_nr]);
    	count++;
-		*area_count(area_dst, page_nr) = count_verify[page_nr] = count;
-		pthread_mutex_unlock(area_mutex(area_dst, page_nr));
+		*area_count(gopts->area_dst, page_nr, gopts) = gopts->count_verify[page_nr] = count;
+		pthread_mutex_unlock(area_mutex(gopts->area_dst, page_nr, gopts));
    }
return NULL;
 }
-static int copy_page_retry(int ufd, unsigned long offset)
+static int copy_page_retry(uffd_global_test_opts_t *gopts, unsigned long offset)
 {
-	return __copy_page(ufd, offset, true, test_uffdio_wp);
+	return __copy_page(gopts, offset, true, gopts->test_uffdio_wp);
 }
pthread_mutex_t uffd_read_mutex = PTHREAD_MUTEX_INITIALIZER;
@@ -131,15 +141,16 @@ pthread_mutex_t uffd_read_mutex = PTHREAD_MUTEX_INITIALIZER;
 static void *uffd_read_thread(void *arg)
 {
    struct uffd_args *args = (struct uffd_args *)arg;
+	uffd_global_test_opts_t *gopts = args->gopts;
    struct uffd_msg msg;
pthread_mutex_unlock(&uffd_read_mutex);
    /* from here cancellation is ok */
for (;;) {
-		if (uffd_read_msg(&msg))
+		if (uffd_read_msg(gopts, &msg))
    		continue;
-		uffd_handle_page_fault(&msg, args);
+		uffd_handle_page_fault(gopts, &msg, args);
    }
return NULL;
@@ -147,32 +158,34 @@ static void *uffd_read_thread(void *arg)
static void *background_thread(void *arg)
 {
-	unsigned long cpu = (unsigned long) arg;
+	struct uffd_args *args = (struct uffd_args *) arg;
+	uffd_global_test_opts_t *gopts = args->gopts;
+	unsigned long cpu = (unsigned long) args->cpu;
    unsigned long page_nr, start_nr, mid_nr, end_nr;
-	start_nr = cpu * nr_pages_per_cpu;
-	end_nr = (cpu+1) * nr_pages_per_cpu;
+	start_nr = cpu * gopts->nr_pages_per_cpu;
+	end_nr = (cpu+1) * gopts->nr_pages_per_cpu;
    mid_nr = (start_nr + end_nr) / 2;
/* Copy the first half of the pages */
    for (page_nr = start_nr; page_nr < mid_nr; page_nr++)
-		copy_page_retry(uffd, page_nr * page_size);
+		copy_page_retry(gopts, page_nr * gopts->page_size);
/*
     * If we need to test uffd-wp, set it up now.  Then we'll have
     * at least the first half of the pages mapped already which
     * can be write-protected for testing
     */
-	if (test_uffdio_wp)
-		wp_range(uffd, (unsigned long)area_dst + start_nr * page_size,
-			nr_pages_per_cpu * page_size, true);
+	if (gopts->test_uffdio_wp)
+		wp_range(gopts->uffd, (unsigned long)gopts->area_dst + start_nr * gopts->page_size,
+			gopts->nr_pages_per_cpu * gopts->page_size, true);
/*
     * Continue the 2nd half of the page copying, handling write
     * protection faults if any
     */
    for (page_nr = mid_nr; page_nr < end_nr; page_nr++)
-		copy_page_retry(uffd, page_nr * page_size);
+		copy_page_retry(gopts, page_nr * gopts->page_size);
return NULL;
 }
@@ -180,17 +193,21 @@ static void *background_thread(void *arg)
 static int stress(struct uffd_args *args)
 {
    unsigned long cpu;
-	pthread_t locking_threads[nr_parallel];
-	pthread_t uffd_threads[nr_parallel];
-	pthread_t background_threads[nr_parallel];
+	uffd_global_test_opts_t *gopts = args->gopts;
+	pthread_t locking_threads[gopts->nr_parallel];
+	pthread_t uffd_threads[gopts->nr_parallel];
+	pthread_t background_threads[gopts->nr_parallel];
-	finished = 0;
-	for (cpu = 0; cpu < nr_parallel; cpu++) {
+	gopts->finished = 0;
+	for (cpu = 0; cpu < gopts->nr_parallel; cpu++) {
    	if (pthread_create(&locking_threads[cpu], &attr,
-				   locking_thread, (void *)cpu))
+				   locking_thread, (void *)&args[cpu]))
    		return 1;
    	if (bounces & BOUNCE_POLL) {
-			if (pthread_create(&uffd_threads[cpu], &attr, uffd_poll_thread, &args[cpu]))
+			if (pthread_create(&uffd_threads[cpu],
+					   &attr,
+					   uffd_poll_thread,
+					   (void *) &args[cpu]))
    			err("uffd_poll_thread create");
    	} else {
    		if (pthread_create(&uffd_threads[cpu], &attr,
@@ -200,10 +217,10 @@ static int stress(struct uffd_args *args)
    		pthread_mutex_lock(&uffd_read_mutex);
    	}
    	if (pthread_create(&background_threads[cpu], &attr,
-				   background_thread, (void *)cpu))
+				   background_thread, (void *)&args[cpu]))
    		return 1;
    }
-	for (cpu = 0; cpu < nr_parallel; cpu++)
+	for (cpu = 0; cpu < gopts->nr_parallel; cpu++)
    	if (pthread_join(background_threads[cpu], NULL))
    		return 1;
@@ -216,17 +233,17 @@ static int stress(struct uffd_args *args)
     * UFFDIO_COPY without writing zero pages into area_dst
     * because the background threads already completed).
     */
-	uffd_test_ops->release_pages(area_src);
+	uffd_test_ops->release_pages(gopts, gopts->area_src);
-	finished = 1;
-	for (cpu = 0; cpu < nr_parallel; cpu++)
+	gopts->finished = 1;
+	for (cpu = 0; cpu < gopts->nr_parallel; cpu++)
    	if (pthread_join(locking_threads[cpu], NULL))
    		return 1;
-	for (cpu = 0; cpu < nr_parallel; cpu++) {
+	for (cpu = 0; cpu < gopts->nr_parallel; cpu++) {
    	char c;
    	if (bounces & BOUNCE_POLL) {
-			if (write(pipefd[cpu*2+1], &c, 1) != 1)
+			if (write(gopts->pipefd[cpu*2+1], &c, 1) != 1)
    			err("pipefd write error");
    		if (pthread_join(uffd_threads[cpu],
    				 (void *)&args[cpu]))
@@ -242,26 +259,26 @@ static int stress(struct uffd_args *args)
    return 0;
 }
-static int userfaultfd_stress(void)
+static int userfaultfd_stress(uffd_global_test_opts_t *gopts)
 {
    void *area;
    unsigned long nr;
-	struct uffd_args args[nr_parallel];
-	uint64_t mem_size = nr_pages * page_size;
+	struct uffd_args args[gopts->nr_parallel];
+	uint64_t mem_size = gopts->nr_pages * gopts->page_size;
    int flags = 0;
-	memset(args, 0, sizeof(struct uffd_args) * nr_parallel);
+	memset(args, 0, sizeof(struct uffd_args) * gopts->nr_parallel);
-	if (features & UFFD_FEATURE_WP_UNPOPULATED && test_type == TEST_ANON)
+	if (features & UFFD_FEATURE_WP_UNPOPULATED && gopts->test_type == TEST_ANON)
    	flags = UFFD_FEATURE_WP_UNPOPULATED;
-	if (uffd_test_ctx_init(flags, NULL))
+	if (uffd_test_ctx_init(gopts, flags, NULL))
    	err("context init failed");
-	if (posix_memalign(&area, page_size, page_size))
+	if (posix_memalign(&area, gopts->page_size, gopts->page_size))
    	err("out of memory");
    zeropage = area;
-	bzero(zeropage, page_size);
+	bzero(zeropage, gopts->page_size);
pthread_mutex_lock(&uffd_read_mutex);
@@ -284,18 +301,18 @@ static int userfaultfd_stress(void)
    	fflush(stdout);
if (bounces & BOUNCE_POLL)
-			fcntl(uffd, F_SETFL, uffd_flags | O_NONBLOCK);
+			fcntl(gopts->uffd, F_SETFL, gopts->uffd_flags | O_NONBLOCK);
    	else
-			fcntl(uffd, F_SETFL, uffd_flags & ~O_NONBLOCK);
+			fcntl(gopts->uffd, F_SETFL, gopts->uffd_flags & ~O_NONBLOCK);
/* register */
-		if (uffd_register(uffd, area_dst, mem_size,
-				  true, test_uffdio_wp, false))
+		if (uffd_register(gopts->uffd, gopts->area_dst, mem_size,
+				  true, gopts->test_uffdio_wp, false))
    		err("register failure");
-		if (area_dst_alias) {
-			if (uffd_register(uffd, area_dst_alias, mem_size,
-					  true, test_uffdio_wp, false))
+		if (gopts->area_dst_alias) {
+			if (uffd_register(gopts->uffd, gopts->area_dst_alias, mem_size,
+					  true, gopts->test_uffdio_wp, false))
    			err("register failure alias");
    	}
@@ -323,87 +340,88 @@ static int userfaultfd_stress(void)
    	 * MADV_DONTNEED only after the UFFDIO_REGISTER, so it's
    	 * required to MADV_DONTNEED here.
    	 */
-		uffd_test_ops->release_pages(area_dst);
+		uffd_test_ops->release_pages(gopts, gopts->area_dst);
-		uffd_stats_reset(args, nr_parallel);
+		uffd_stats_reset(gopts, args, gopts->nr_parallel);
/* bounce pass */
    	if (stress(args)) {
-			uffd_test_ctx_clear();
+			uffd_test_ctx_clear(gopts);
    		return 1;
    	}
/* Clear all the write protections if there is any */
-		if (test_uffdio_wp)
-			wp_range(uffd, (unsigned long)area_dst,
-				 nr_pages * page_size, false);
+		if (gopts->test_uffdio_wp)
+			wp_range(gopts->uffd, (unsigned long)gopts->area_dst,
+				 gopts->nr_pages * gopts->page_size, false);
/* unregister */
-		if (uffd_unregister(uffd, area_dst, mem_size))
+		if (uffd_unregister(gopts->uffd, gopts->area_dst, mem_size))
    		err("unregister failure");
-		if (area_dst_alias) {
-			if (uffd_unregister(uffd, area_dst_alias, mem_size))
+		if (gopts->area_dst_alias) {
+			if (uffd_unregister(gopts->uffd, gopts->area_dst_alias, mem_size))
    			err("unregister failure alias");
    	}
/* verification */
    	if (bounces & BOUNCE_VERIFY)
-			for (nr = 0; nr < nr_pages; nr++)
-				if (*area_count(area_dst, nr) != count_verify[nr])
+			for (nr = 0; nr < gopts->nr_pages; nr++)
+				if (*area_count(gopts->area_dst, nr, gopts) !=
+						gopts->count_verify[nr])
    				err("error area_count %llu %llu %lu\n",
-					    *area_count(area_src, nr),
-					    count_verify[nr], nr);
+					    *area_count(gopts->area_src, nr, gopts),
+					    gopts->count_verify[nr], nr);
/* prepare next bounce */
-		swap(area_src, area_dst);
+		swap(gopts->area_src, gopts->area_dst);
-		swap(area_src_alias, area_dst_alias);
+		swap(gopts->area_src_alias, gopts->area_dst_alias);
-		uffd_stats_report(args, nr_parallel);
+		uffd_stats_report(args, gopts->nr_parallel);
    }
-	uffd_test_ctx_clear();
+	uffd_test_ctx_clear(gopts);
return 0;
 }
-static void set_test_type(const char *type)
+static void set_test_type(uffd_global_test_opts_t *gopts, const char *type)
 {
    if (!strcmp(type, "anon")) {
-		test_type = TEST_ANON;
+		gopts->test_type = TEST_ANON;
    	uffd_test_ops = &anon_uffd_test_ops;
    } else if (!strcmp(type, "hugetlb")) {
-		test_type = TEST_HUGETLB;
+		gopts->test_type = TEST_HUGETLB;
    	uffd_test_ops = &hugetlb_uffd_test_ops;
-		map_shared = true;
+		gopts->map_shared = true;
    } else if (!strcmp(type, "hugetlb-private")) {
-		test_type = TEST_HUGETLB;
+		gopts->test_type = TEST_HUGETLB;
    	uffd_test_ops = &hugetlb_uffd_test_ops;
    } else if (!strcmp(type, "shmem")) {
-		map_shared = true;
-		test_type = TEST_SHMEM;
+		gopts->map_shared = true;
+		gopts->test_type = TEST_SHMEM;
    	uffd_test_ops = &shmem_uffd_test_ops;
    } else if (!strcmp(type, "shmem-private")) {
-		test_type = TEST_SHMEM;
+		gopts->test_type = TEST_SHMEM;
    	uffd_test_ops = &shmem_uffd_test_ops;
    }
 }
-static void parse_test_type_arg(const char *raw_type)
+static void parse_test_type_arg(uffd_global_test_opts_t *gopts, const char *raw_type)
 {
-	set_test_type(raw_type);
+	set_test_type(gopts, raw_type);
-	if (!test_type)
+	if (!gopts->test_type)
    	err("failed to parse test type argument: '%s'", raw_type);
-	if (test_type == TEST_HUGETLB)
-		page_size = default_huge_page_size();
+	if (gopts->test_type == TEST_HUGETLB)
+		gopts->page_size = default_huge_page_size();
    else
-		page_size = sysconf(_SC_PAGE_SIZE);
+		gopts->page_size = sysconf(_SC_PAGE_SIZE);
-	if (!page_size)
+	if (!gopts->page_size)
    	err("Unable to determine page size");
-	if ((unsigned long) area_count(NULL, 0) + sizeof(unsigned long long) * 2
-	    > page_size)
+	if ((unsigned long) area_count(NULL, 0, gopts) + sizeof(unsigned long long) * 2
+	    > gopts->page_size)
    	err("Impossible to run this test");
/*
@@ -415,21 +433,21 @@ static void parse_test_type_arg(const char *raw_type)
    if (uffd_get_features(&features) && errno == ENOENT)
    	ksft_exit_skip("failed to get available features (%d)\n", errno);
-	test_uffdio_wp = test_uffdio_wp &&
+	gopts->test_uffdio_wp = gopts->test_uffdio_wp &&
    	(features & UFFD_FEATURE_PAGEFAULT_FLAG_WP);
-	if (test_type != TEST_ANON && !(features & UFFD_FEATURE_WP_HUGETLBFS_SHMEM))
-		test_uffdio_wp = false;
+	if (gopts->test_type != TEST_ANON && !(features & UFFD_FEATURE_WP_HUGETLBFS_SHMEM))
+		gopts->test_uffdio_wp = false;
-	close(uffd);
-	uffd = -1;
+	close(gopts->uffd);
+	gopts->uffd = -1;
 }
static void sigalrm(int sig)
 {
    if (sig != SIGALRM)
    	abort();
-	test_uffdio_copy_eexist = true;
+	gopts->test_uffdio_copy_eexist = true;
    alarm(ALARM_INTERVAL_SECS);
 }
@@ -438,6 +456,8 @@ int main(int argc, char **argv)
    unsigned long nr_cpus;
    size_t bytes;
+	gopts = (uffd_global_test_opts_t *) malloc(sizeof(uffd_global_test_opts_t));
+
    if (argc < 4)
    	usage();
@@ -445,11 +465,11 @@ int main(int argc, char **argv)
    	err("failed to arm SIGALRM");
    alarm(ALARM_INTERVAL_SECS);
-	parse_test_type_arg(argv[1]);
+	parse_test_type_arg(gopts, argv[1]);
    bytes = atol(argv[2]) * 1024 * 1024;
-	if (test_type == TEST_HUGETLB &&
-	   get_free_hugepages() < bytes / page_size) {
+	if (gopts->test_type == TEST_HUGETLB &&
+	   get_free_hugepages() < bytes / gopts->page_size) {
    	printf("skip: Skipping userfaultfd... not enough hugepages\n");
    	return KSFT_SKIP;
    }
@@ -459,15 +479,15 @@ int main(int argc, char **argv)
    	/* Don't let calculation below go to zero. */
    	ksft_print_msg("_SC_NPROCESSORS_ONLN (%lu) too large, capping nr_threads to 32\n",
    		       nr_cpus);
-		nr_parallel = 32;
+		gopts->nr_parallel = 32;
    } else {
-		nr_parallel = nr_cpus;
+		gopts->nr_parallel = nr_cpus;
    }
-	nr_pages_per_cpu = bytes / page_size / nr_parallel;
-	if (!nr_pages_per_cpu) {
+	gopts->nr_pages_per_cpu = bytes / gopts->page_size / gopts->nr_parallel;
+	if (!gopts->nr_pages_per_cpu) {
    	_err("pages_per_cpu = 0, cannot test (%lu / %lu / %lu)",
-			bytes, page_size, nr_parallel);
+			bytes, gopts->page_size, gopts->nr_parallel);
    	usage();
    }
@@ -476,11 +496,11 @@ int main(int argc, char **argv)
    	_err("invalid bounces");
    	usage();
    }
-	nr_pages = nr_pages_per_cpu * nr_parallel;
+	gopts->nr_pages = gopts->nr_pages_per_cpu * gopts->nr_parallel;
printf("nr_pages: %lu, nr_pages_per_cpu: %lu\n",
-	       nr_pages, nr_pages_per_cpu);
-	return userfaultfd_stress();
+	       gopts->nr_pages, gopts->nr_pages_per_cpu);
+	return userfaultfd_stress(gopts);
 }
#else /* __NR_userfaultfd */
diff --git a/tools/testing/selftests/mm/uffd-unit-tests.c b/tools/testing/selftests/mm/uffd-unit-tests.c
index ee9b407e893e..101eaca2662e 100644
--- a/tools/testing/selftests/mm/uffd-unit-tests.c
+++ b/tools/testing/selftests/mm/uffd-unit-tests.c
@@ -76,7 +76,7 @@ struct uffd_test_args {
 typedef struct uffd_test_args uffd_test_args_t;
/* Returns: UFFD_TEST_* */
-typedef void (*uffd_test_fn)(uffd_test_args_t *);
+typedef void (*uffd_test_fn)(uffd_global_test_opts_t *, uffd_test_args_t *);
typedef struct {
    const char *name;
@@ -181,33 +181,6 @@ static int test_uffd_api(bool use_dev)
    return 1;
 }
-/*
- * This function initializes the global variables.  TODO: remove global
- * vars and then remove this.
- */
-static int
-uffd_setup_environment(uffd_test_args_t *args, uffd_test_case_t *test,
-		       mem_type_t *mem_type, const char **errmsg)
-{
-	map_shared = mem_type->shared;
-	uffd_test_ops = mem_type->mem_ops;
-	uffd_test_case_ops = test->test_case_ops;
-
-	if (mem_type->mem_flag & (MEM_HUGETLB_PRIVATE | MEM_HUGETLB))
-		page_size = default_huge_page_size();
-	else
-		page_size = psize();
-
-	/* Ensure we have at least 2 pages */
-	nr_pages = MAX(UFFD_TEST_MEM_SIZE, page_size * 2) / page_size;
-	/* TODO: remove this global var.. it's so ugly */
-	nr_parallel = 1;
-
-	/* Initialize test arguments */
-	args->mem_type = mem_type;
-
-	return uffd_test_ctx_init(test->uffd_feature_required, errmsg);
-}
static bool uffd_feature_supported(uffd_test_case_t *test)
 {
@@ -237,7 +210,8 @@ static int pagemap_open(void)
    } while (0)
typedef struct {
-	int parent_uffd, child_uffd;
+	uffd_global_test_opts_t *gopts;
+	int child_uffd;
 } fork_event_args;
static void *fork_event_consumer(void *data)
@@ -245,10 +219,10 @@ static void *fork_event_consumer(void *data)
    fork_event_args *args = data;
    struct uffd_msg msg = { 0 };
-	ready_for_fork = true;
+	args->gopts->ready_for_fork = true;
/* Read until a full msg received */
-	while (uffd_read_msg(&msg));
+	while (uffd_read_msg(args->gopts, &msg));
if (msg.event != UFFD_EVENT_FORK)
    	err("wrong message: %u\n", msg.event);
@@ -304,9 +278,9 @@ static void unpin_pages(pin_args *args)
    args->pinned = false;
 }
-static int pagemap_test_fork(int uffd, bool with_event, bool test_pin)
+static int pagemap_test_fork(uffd_global_test_opts_t *gopts, bool with_event, bool test_pin)
 {
-	fork_event_args args = { .parent_uffd = uffd, .child_uffd = -1 };
+	fork_event_args args = { .gopts = gopts, .child_uffd = -1 };
    pthread_t thread;
    pid_t child;
    uint64_t value;
@@ -314,10 +288,10 @@ static int pagemap_test_fork(int uffd, bool with_event, bool test_pin)
/* Prepare a thread to resolve EVENT_FORK */
    if (with_event) {
-		ready_for_fork = false;
+		gopts->ready_for_fork = false;
    	if (pthread_create(&thread, NULL, fork_event_consumer, &args))
    		err("pthread_create()");
-		while (!ready_for_fork)
+		while (!gopts->ready_for_fork)
    		; /* Wait for the poll_thread to start executing before forking */
    }
@@ -328,14 +302,14 @@ static int pagemap_test_fork(int uffd, bool with_event, bool test_pin)
fd = pagemap_open();
-		if (test_pin && pin_pages(&args, area_dst, page_size))
+		if (test_pin && pin_pages(&args, gopts->area_dst, gopts->page_size))
    		/*
    		 * Normally when reach here we have pinned in
    		 * previous tests, so shouldn't fail anymore
    		 */
    		err("pin page failed in child");
-		value = pagemap_get_entry(fd, area_dst);
+		value = pagemap_get_entry(fd, gopts->area_dst);
    	/*
    	 * After fork(), we should handle uffd-wp bit differently:
    	 *
@@ -361,70 +335,71 @@ static int pagemap_test_fork(int uffd, bool with_event, bool test_pin)
    return result;
 }
-static void uffd_wp_unpopulated_test(uffd_test_args_t __unused *args)
+static void uffd_wp_unpopulated_test(uffd_global_test_opts_t *gopts,
+				     uffd_test_args_t __unused *args)
 {
    uint64_t value;
    int pagemap_fd;
-	if (uffd_register(uffd, area_dst, nr_pages * page_size,
+	if (uffd_register(gopts->uffd, gopts->area_dst, gopts->nr_pages * gopts->page_size,
    		  false, true, false))
    	err("register failed");
pagemap_fd = pagemap_open();
/* Test applying pte marker to anon unpopulated */
-	wp_range(uffd, (uint64_t)area_dst, page_size, true);
-	value = pagemap_get_entry(pagemap_fd, area_dst);
+	wp_range(gopts->uffd, (uint64_t)gopts->area_dst, gopts->page_size, true);
+	value = pagemap_get_entry(pagemap_fd, gopts->area_dst);
    pagemap_check_wp(value, true);
/* Test unprotect on anon pte marker */
-	wp_range(uffd, (uint64_t)area_dst, page_size, false);
-	value = pagemap_get_entry(pagemap_fd, area_dst);
+	wp_range(gopts->uffd, (uint64_t)gopts->area_dst, gopts->page_size, false);
+	value = pagemap_get_entry(pagemap_fd, gopts->area_dst);
    pagemap_check_wp(value, false);
/* Test zap on anon marker */
-	wp_range(uffd, (uint64_t)area_dst, page_size, true);
-	if (madvise(area_dst, page_size, MADV_DONTNEED))
+	wp_range(gopts->uffd, (uint64_t)gopts->area_dst, gopts->page_size, true);
+	if (madvise(gopts->area_dst, gopts->page_size, MADV_DONTNEED))
    	err("madvise(MADV_DONTNEED) failed");
-	value = pagemap_get_entry(pagemap_fd, area_dst);
+	value = pagemap_get_entry(pagemap_fd, gopts->area_dst);
    pagemap_check_wp(value, false);
/* Test fault in after marker removed */
-	*area_dst = 1;
-	value = pagemap_get_entry(pagemap_fd, area_dst);
+	*gopts->area_dst = 1;
+	value = pagemap_get_entry(pagemap_fd, gopts->area_dst);
    pagemap_check_wp(value, false);
    /* Drop it to make pte none again */
-	if (madvise(area_dst, page_size, MADV_DONTNEED))
+	if (madvise(gopts->area_dst, gopts->page_size, MADV_DONTNEED))
    	err("madvise(MADV_DONTNEED) failed");
/* Test read-zero-page upon pte marker */
-	wp_range(uffd, (uint64_t)area_dst, page_size, true);
-	*(volatile char *)area_dst;
+	wp_range(gopts->uffd, (uint64_t)gopts->area_dst, gopts->page_size, true);
+	*(volatile char *)gopts->area_dst;
    /* Drop it to make pte none again */
-	if (madvise(area_dst, page_size, MADV_DONTNEED))
+	if (madvise(gopts->area_dst, gopts->page_size, MADV_DONTNEED))
    	err("madvise(MADV_DONTNEED) failed");
uffd_test_pass();
 }
-static void uffd_wp_fork_test_common(uffd_test_args_t *args,
+static void uffd_wp_fork_test_common(uffd_global_test_opts_t *gopts, uffd_test_args_t *args,
    			     bool with_event)
 {
    int pagemap_fd;
    uint64_t value;
-	if (uffd_register(uffd, area_dst, nr_pages * page_size,
+	if (uffd_register(gopts->uffd, gopts->area_dst, gopts->nr_pages * gopts->page_size,
    		  false, true, false))
    	err("register failed");
pagemap_fd = pagemap_open();
/* Touch the page */
-	*area_dst = 1;
-	wp_range(uffd, (uint64_t)area_dst, page_size, true);
-	value = pagemap_get_entry(pagemap_fd, area_dst);
+	*gopts->area_dst = 1;
+	wp_range(gopts->uffd, (uint64_t)gopts->area_dst, gopts->page_size, true);
+	value = pagemap_get_entry(pagemap_fd, gopts->area_dst);
    pagemap_check_wp(value, true);
-	if (pagemap_test_fork(uffd, with_event, false)) {
+	if (pagemap_test_fork(gopts, with_event, false)) {
    	uffd_test_fail("Detected %s uffd-wp bit in child in present pte",
    		       with_event ? "missing" : "stall");
    	goto out;
@@ -442,79 +417,80 @@ static void uffd_wp_fork_test_common(uffd_test_args_t *args,
     * to expose pte markers.
     */
    if (args->mem_type->shared) {
-		if (madvise(area_dst, page_size, MADV_DONTNEED))
+		if (madvise(gopts->area_dst, gopts->page_size, MADV_DONTNEED))
    		err("MADV_DONTNEED");
    } else {
    	/*
    	 * NOTE: ignore retval because private-hugetlb doesn't yet
    	 * support swapping, so it could fail.
    	 */
-		madvise(area_dst, page_size, MADV_PAGEOUT);
+		madvise(gopts->area_dst, gopts->page_size, MADV_PAGEOUT);
    }
/* Uffd-wp should persist even swapped out */
-	value = pagemap_get_entry(pagemap_fd, area_dst);
+	value = pagemap_get_entry(pagemap_fd, gopts->area_dst);
    pagemap_check_wp(value, true);
-	if (pagemap_test_fork(uffd, with_event, false)) {
+	if (pagemap_test_fork(gopts, with_event, false)) {
    	uffd_test_fail("Detected %s uffd-wp bit in child in zapped pte",
    		       with_event ? "missing" : "stall");
    	goto out;
    }
/* Unprotect; this tests swap pte modifications */
-	wp_range(uffd, (uint64_t)area_dst, page_size, false);
-	value = pagemap_get_entry(pagemap_fd, area_dst);
+	wp_range(gopts->uffd, (uint64_t)gopts->area_dst, gopts->page_size, false);
+	value = pagemap_get_entry(pagemap_fd, gopts->area_dst);
    pagemap_check_wp(value, false);
/* Fault in the page from disk */
-	*area_dst = 2;
-	value = pagemap_get_entry(pagemap_fd, area_dst);
+	*gopts->area_dst = 2;
+	value = pagemap_get_entry(pagemap_fd, gopts->area_dst);
    pagemap_check_wp(value, false);
    uffd_test_pass();
 out:
-	if (uffd_unregister(uffd, area_dst, nr_pages * page_size))
+	if (uffd_unregister(gopts->uffd, gopts->area_dst, gopts->nr_pages * gopts->page_size))
    	err("unregister failed");
    close(pagemap_fd);
 }
-static void uffd_wp_fork_test(uffd_test_args_t *args)
+static void uffd_wp_fork_test(uffd_global_test_opts_t *gopts, uffd_test_args_t *args)
 {
-	uffd_wp_fork_test_common(args, false);
+	uffd_wp_fork_test_common(gopts, args, false);
 }
-static void uffd_wp_fork_with_event_test(uffd_test_args_t *args)
+static void uffd_wp_fork_with_event_test(uffd_global_test_opts_t *gopts, uffd_test_args_t *args)
 {
-	uffd_wp_fork_test_common(args, true);
+	uffd_wp_fork_test_common(gopts, args, true);
 }
-static void uffd_wp_fork_pin_test_common(uffd_test_args_t __unused *args,
+static void uffd_wp_fork_pin_test_common(uffd_global_test_opts_t *gopts,
+					 uffd_test_args_t __unused *args,
    				 bool with_event)
 {
    int pagemap_fd;
    pin_args pin_args = {};
-	if (uffd_register(uffd, area_dst, page_size, false, true, false))
+	if (uffd_register(gopts->uffd, gopts->area_dst, gopts->page_size, false, true, false))
    	err("register failed");
pagemap_fd = pagemap_open();
/* Touch the page */
-	*area_dst = 1;
-	wp_range(uffd, (uint64_t)area_dst, page_size, true);
+	*gopts->area_dst = 1;
+	wp_range(gopts->uffd, (uint64_t)gopts->area_dst, gopts->page_size, true);
/*
     * 1. First pin, then fork().  This tests fork() special path when
     * doing early CoW if the page is private.
     */
-	if (pin_pages(&pin_args, area_dst, page_size)) {
+	if (pin_pages(&pin_args, gopts->area_dst, gopts->page_size)) {
    	uffd_test_skip("Possibly CONFIG_GUP_TEST missing "
    		       "or unprivileged");
    	close(pagemap_fd);
-		uffd_unregister(uffd, area_dst, page_size);
+		uffd_unregister(gopts->uffd, gopts->area_dst, gopts->page_size);
    	return;
    }
-	if (pagemap_test_fork(uffd, with_event, false)) {
+	if (pagemap_test_fork(gopts, with_event, false)) {
    	uffd_test_fail("Detected %s uffd-wp bit in early CoW of fork()",
    		       with_event ? "missing" : "stall");
    	unpin_pages(&pin_args);
@@ -527,49 +503,50 @@ static void uffd_wp_fork_pin_test_common(uffd_test_args_t __unused *args,
     * 2. First fork(), then pin (in the child, where test_pin==true).
     * This tests COR, aka, page unsharing on private memories.
     */
-	if (pagemap_test_fork(uffd, with_event, true)) {
+	if (pagemap_test_fork(gopts, with_event, true)) {
    	uffd_test_fail("Detected %s uffd-wp bit when RO pin",
    		       with_event ? "missing" : "stall");
    	goto out;
    }
    uffd_test_pass();
 out:
-	if (uffd_unregister(uffd, area_dst, page_size))
+	if (uffd_unregister(gopts->uffd, gopts->area_dst, gopts->page_size))
    	err("register failed");
    close(pagemap_fd);
 }
-static void uffd_wp_fork_pin_test(uffd_test_args_t *args)
+static void uffd_wp_fork_pin_test(uffd_global_test_opts_t *gopts, uffd_test_args_t *args)
 {
-	uffd_wp_fork_pin_test_common(args, false);
+	uffd_wp_fork_pin_test_common(gopts, args, false);
 }
-static void uffd_wp_fork_pin_with_event_test(uffd_test_args_t *args)
+static void uffd_wp_fork_pin_with_event_test(uffd_global_test_opts_t *gopts, uffd_test_args_t *args)
 {
-	uffd_wp_fork_pin_test_common(args, true);
+	uffd_wp_fork_pin_test_common(gopts, args, true);
 }
-static void check_memory_contents(char *p)
+static void check_memory_contents(uffd_global_test_opts_t *gopts, char *p)
 {
    unsigned long i, j;
    uint8_t expected_byte;
-	for (i = 0; i < nr_pages; ++i) {
+	for (i = 0; i < gopts->nr_pages; ++i) {
    	expected_byte = ~((uint8_t)(i % ((uint8_t)-1)));
-		for (j = 0; j < page_size; j++) {
-			uint8_t v = *(uint8_t *)(p + (i * page_size) + j);
+		for (j = 0; j < gopts->page_size; j++) {
+			uint8_t v = *(uint8_t *)(p + (i * gopts->page_size) + j);
    		if (v != expected_byte)
    			err("unexpected page contents");
    	}
    }
 }
-static void uffd_minor_test_common(bool test_collapse, bool test_wp)
+static void uffd_minor_test_common(uffd_global_test_opts_t *gopts, bool test_collapse, bool test_wp)
 {
    unsigned long p;
    pthread_t uffd_mon;
    char c;
    struct uffd_args args = { 0 };
+	args.gopts = gopts;
/*
     * NOTE: MADV_COLLAPSE is not yet compatible with WP, so testing
@@ -577,7 +554,7 @@ static void uffd_minor_test_common(bool test_collapse, bool test_wp)
     */
    assert(!(test_collapse && test_wp));
-	if (uffd_register(uffd, area_dst_alias, nr_pages * page_size,
+	if (uffd_register(gopts->uffd, gopts->area_dst_alias, gopts->nr_pages * gopts->page_size,
    		  /* NOTE! MADV_COLLAPSE may not work with uffd-wp */
    		  false, test_wp, true))
    	err("register failure");
@@ -586,9 +563,9 @@ static void uffd_minor_test_common(bool test_collapse, bool test_wp)
     * After registering with UFFD, populate the non-UFFD-registered side of
     * the shared mapping. This should *not* trigger any UFFD minor faults.
     */
-	for (p = 0; p < nr_pages; ++p)
-		memset(area_dst + (p * page_size), p % ((uint8_t)-1),
-		       page_size);
+	for (p = 0; p < gopts->nr_pages; ++p)
+		memset(gopts->area_dst + (p * gopts->page_size), p % ((uint8_t)-1),
+		       gopts->page_size);
args.apply_wp = test_wp;
    if (pthread_create(&uffd_mon, NULL, uffd_poll_thread, &args))
@@ -600,50 +577,51 @@ static void uffd_minor_test_common(bool test_collapse, bool test_wp)
     * fault. uffd_poll_thread will resolve the fault by bit-flipping the
     * page's contents, and then issuing a CONTINUE ioctl.
     */
-	check_memory_contents(area_dst_alias);
+	check_memory_contents(gopts, gopts->area_dst_alias);
-	if (write(pipefd[1], &c, sizeof(c)) != sizeof(c))
+	if (write(gopts->pipefd[1], &c, sizeof(c)) != sizeof(c))
    	err("pipe write");
    if (pthread_join(uffd_mon, NULL))
    	err("join() failed");
if (test_collapse) {
-		if (madvise(area_dst_alias, nr_pages * page_size,
+		if (madvise(gopts->area_dst_alias, gopts->nr_pages * gopts->page_size,
    		    MADV_COLLAPSE)) {
    		/* It's fine to fail for this one... */
    		uffd_test_skip("MADV_COLLAPSE failed");
    		return;
    	}
-		uffd_test_ops->check_pmd_mapping(area_dst,
-						 nr_pages * page_size /
+		uffd_test_ops->check_pmd_mapping(gopts,
+						 gopts->area_dst,
+						 gopts->nr_pages * gopts->page_size /
    					 read_pmd_pagesize());
    	/*
    	 * This won't cause uffd-fault - it purely just makes sure there
    	 * was no corruption.
    	 */
-		check_memory_contents(area_dst_alias);
+		check_memory_contents(gopts, gopts->area_dst_alias);
    }
-	if (args.missing_faults != 0 || args.minor_faults != nr_pages)
+	if (args.missing_faults != 0 || args.minor_faults != gopts->nr_pages)
    	uffd_test_fail("stats check error");
    else
    	uffd_test_pass();
 }
-void uffd_minor_test(uffd_test_args_t __unused *args)
+void uffd_minor_test(uffd_global_test_opts_t *gopts, uffd_test_args_t __unused *args)
 {
-	uffd_minor_test_common(false, false);
+	uffd_minor_test_common(gopts, false, false);
 }
-void uffd_minor_wp_test(uffd_test_args_t __unused *args)
+void uffd_minor_wp_test(uffd_global_test_opts_t *gopts, uffd_test_args_t __unused *args)
 {
-	uffd_minor_test_common(false, true);
+	uffd_minor_test_common(gopts, false, true);
 }
-void uffd_minor_collapse_test(uffd_test_args_t __unused *args)
+void uffd_minor_collapse_test(uffd_global_test_opts_t *gopts, uffd_test_args_t __unused *args)
 {
-	uffd_minor_test_common(true, false);
+	uffd_minor_test_common(gopts, true, false);
 }
static sigjmp_buf jbuf, *sigbuf;
@@ -678,7 +656,7 @@ static void sighndl(int sig, siginfo_t __unused *siginfo, void __unused *ptr)
  * This also tests UFFD_FEATURE_EVENT_FORK event along with the signal
  * feature. Using monitor thread, verify no userfault events are generated.
  */
-static int faulting_process(int signal_test, bool wp)
+static int faulting_process(uffd_global_test_opts_t *gopts, int signal_test, bool wp)
 {
    unsigned long nr, i;
    unsigned long long count;
@@ -687,7 +665,7 @@ static int faulting_process(int signal_test, bool wp)
    struct sigaction act;
    volatile unsigned long signalled = 0;
-	split_nr_pages = (nr_pages + 1) / 2;
+	split_nr_pages = (gopts->nr_pages + 1) / 2;
if (signal_test) {
    	sigbuf = &jbuf;
@@ -701,7 +679,7 @@ static int faulting_process(int signal_test, bool wp)
for (nr = 0; nr < split_nr_pages; nr++) {
    	volatile int steps = 1;
-		unsigned long offset = nr * page_size;
+		unsigned long offset = nr * gopts->page_size;
if (signal_test) {
    		if (sigsetjmp(*sigbuf, 1) != 0) {
@@ -713,15 +691,15 @@ static int faulting_process(int signal_test, bool wp)
    				if (steps == 1) {
    					/* This is a MISSING request */
    					steps++;
-						if (copy_page(uffd, offset, wp))
+						if (copy_page(gopts, offset, wp))
    						signalled++;
    				} else {
    					/* This is a WP request */
    					assert(steps == 2);
-						wp_range(uffd,
-							 (__u64)area_dst +
+						wp_range(gopts->uffd,
+							 (__u64)gopts->area_dst +
    						 offset,
-							 page_size, false);
+							 gopts->page_size, false);
    				}
    			} else {
    				signalled++;
@@ -730,51 +708,53 @@ static int faulting_process(int signal_test, bool wp)
    		}
    	}
-		count = *area_count(area_dst, nr);
-		if (count != count_verify[nr])
+		count = *area_count(gopts->area_dst, nr, gopts);
+		if (count != gopts->count_verify[nr])
    		err("nr %lu memory corruption %llu %llu\n",
-			    nr, count, count_verify[nr]);
+			    nr, count, gopts->count_verify[nr]);
    	/*
    	 * Trigger write protection if there is by writing
    	 * the same value back.
    	 */
-		*area_count(area_dst, nr) = count;
+		*area_count(gopts->area_dst, nr, gopts) = count;
    }
if (signal_test)
    	return signalled != split_nr_pages;
-	area_dst = mremap(area_dst, nr_pages * page_size,  nr_pages * page_size,
-			  MREMAP_MAYMOVE | MREMAP_FIXED, area_src);
-	if (area_dst == MAP_FAILED)
+	gopts->area_dst = mremap(gopts->area_dst, gopts->nr_pages * gopts->page_size,
+				 gopts->nr_pages * gopts->page_size,
+				 MREMAP_MAYMOVE | MREMAP_FIXED,
+				 gopts->area_src);
+	if (gopts->area_dst == MAP_FAILED)
    	err("mremap");
    /* Reset area_src since we just clobbered it */
-	area_src = NULL;
+	gopts->area_src = NULL;
-	for (; nr < nr_pages; nr++) {
-		count = *area_count(area_dst, nr);
-		if (count != count_verify[nr]) {
+	for (; nr < gopts->nr_pages; nr++) {
+		count = *area_count(gopts->area_dst, nr, gopts);
+		if (count != gopts->count_verify[nr]) {
    		err("nr %lu memory corruption %llu %llu\n",
-			    nr, count, count_verify[nr]);
+			    nr, count, gopts->count_verify[nr]);
    	}
    	/*
    	 * Trigger write protection if there is by writing
    	 * the same value back.
    	 */
-		*area_count(area_dst, nr) = count;
+		*area_count(gopts->area_dst, nr, gopts) = count;
    }
-	uffd_test_ops->release_pages(area_dst);
+	uffd_test_ops->release_pages(gopts, gopts->area_dst);
-	for (nr = 0; nr < nr_pages; nr++)
-		for (i = 0; i < page_size; i++)
-			if (*(area_dst + nr * page_size + i) != 0)
+	for (nr = 0; nr < gopts->nr_pages; nr++)
+		for (i = 0; i < gopts->page_size; i++)
+			if (*(gopts->area_dst + nr * gopts->page_size + i) != 0)
    			err("page %lu offset %lu is not zero", nr, i);
return 0;
 }
-static void uffd_sigbus_test_common(bool wp)
+static void uffd_sigbus_test_common(uffd_global_test_opts_t *gopts, bool wp)
 {
    unsigned long userfaults;
    pthread_t uffd_mon;
@@ -782,25 +762,26 @@ static void uffd_sigbus_test_common(bool wp)
    int err;
    char c;
    struct uffd_args args = { 0 };
+	args.gopts = gopts;
-	ready_for_fork = false;
+	gopts->ready_for_fork = false;
-	fcntl(uffd, F_SETFL, uffd_flags | O_NONBLOCK);
+	fcntl(gopts->uffd, F_SETFL, gopts->uffd_flags | O_NONBLOCK);
-	if (uffd_register(uffd, area_dst, nr_pages * page_size,
+	if (uffd_register(gopts->uffd, gopts->area_dst, gopts->nr_pages * gopts->page_size,
    		  true, wp, false))
    	err("register failure");
-	if (faulting_process(1, wp))
+	if (faulting_process(gopts, 1, wp))
    	err("faulting process failed");
-	uffd_test_ops->release_pages(area_dst);
+	uffd_test_ops->release_pages(gopts, gopts->area_dst);
args.apply_wp = wp;
    if (pthread_create(&uffd_mon, NULL, uffd_poll_thread, &args))
    	err("uffd_poll_thread create");
-	while (!ready_for_fork)
+	while (!gopts->ready_for_fork)
    	; /* Wait for the poll_thread to start executing before forking */
pid = fork();
@@ -808,12 +789,12 @@ static void uffd_sigbus_test_common(bool wp)
    	err("fork");
if (!pid)
-		exit(faulting_process(2, wp));
+		exit(faulting_process(gopts, 2, wp));
waitpid(pid, &err, 0);
    if (err)
    	err("faulting process failed");
-	if (write(pipefd[1], &c, sizeof(c)) != sizeof(c))
+	if (write(gopts->pipefd[1], &c, sizeof(c)) != sizeof(c))
    	err("pipe write");
    if (pthread_join(uffd_mon, (void **)&userfaults))
    	err("pthread_join()");
@@ -824,28 +805,29 @@ static void uffd_sigbus_test_common(bool wp)
    	uffd_test_pass();
 }
-static void uffd_sigbus_test(uffd_test_args_t __unused *args)
+static void uffd_sigbus_test(uffd_global_test_opts_t *gopts, uffd_test_args_t __unused *args)
 {
-	uffd_sigbus_test_common(false);
+	uffd_sigbus_test_common(gopts, false);
 }
-static void uffd_sigbus_wp_test(uffd_test_args_t __unused *args)
+static void uffd_sigbus_wp_test(uffd_global_test_opts_t *gopts, uffd_test_args_t __unused *args)
 {
-	uffd_sigbus_test_common(true);
+	uffd_sigbus_test_common(gopts, true);
 }
-static void uffd_events_test_common(bool wp)
+static void uffd_events_test_common(uffd_global_test_opts_t *gopts, bool wp)
 {
    pthread_t uffd_mon;
    pid_t pid;
    int err;
    char c;
    struct uffd_args args = { 0 };
+	args.gopts = gopts;
-	ready_for_fork = false;
+	gopts->ready_for_fork = false;
-	fcntl(uffd, F_SETFL, uffd_flags | O_NONBLOCK);
-	if (uffd_register(uffd, area_dst, nr_pages * page_size,
+	fcntl(gopts->uffd, F_SETFL, gopts->uffd_flags | O_NONBLOCK);
+	if (uffd_register(gopts->uffd, gopts->area_dst, gopts->nr_pages * gopts->page_size,
    		  true, wp, false))
    	err("register failure");
@@ -853,7 +835,7 @@ static void uffd_events_test_common(bool wp)
    if (pthread_create(&uffd_mon, NULL, uffd_poll_thread, &args))
    	err("uffd_poll_thread create");
-	while (!ready_for_fork)
+	while (!gopts->ready_for_fork)
    	; /* Wait for the poll_thread to start executing before forking */
pid = fork();
@@ -861,39 +843,39 @@ static void uffd_events_test_common(bool wp)
    	err("fork");
if (!pid)
-		exit(faulting_process(0, wp));
+		exit(faulting_process(gopts, 0, wp));
waitpid(pid, &err, 0);
    if (err)
    	err("faulting process failed");
-	if (write(pipefd[1], &c, sizeof(c)) != sizeof(c))
+	if (write(gopts->pipefd[1], &c, sizeof(c)) != sizeof(c))
    	err("pipe write");
    if (pthread_join(uffd_mon, NULL))
    	err("pthread_join()");
-	if (args.missing_faults != nr_pages)
+	if (args.missing_faults != gopts->nr_pages)
    	uffd_test_fail("Fault counts wrong");
    else
    	uffd_test_pass();
 }
-static void uffd_events_test(uffd_test_args_t __unused *args)
+static void uffd_events_test(uffd_global_test_opts_t *gopts, uffd_test_args_t __unused *args)
 {
-	uffd_events_test_common(false);
+	uffd_events_test_common(gopts, false);
 }
-static void uffd_events_wp_test(uffd_test_args_t __unused *args)
+static void uffd_events_wp_test(uffd_global_test_opts_t *gopts, uffd_test_args_t __unused *args)
 {
-	uffd_events_test_common(true);
+	uffd_events_test_common(gopts, true);
 }
-static void retry_uffdio_zeropage(int ufd,
+static void retry_uffdio_zeropage(uffd_global_test_opts_t *gopts,
    			  struct uffdio_zeropage *uffdio_zeropage)
 {
-	uffd_test_ops->alias_mapping(&uffdio_zeropage->range.start,
+	uffd_test_ops->alias_mapping(gopts, &uffdio_zeropage->range.start,
    			     uffdio_zeropage->range.len,
    			     0);
-	if (ioctl(ufd, UFFDIO_ZEROPAGE, uffdio_zeropage)) {
+	if (ioctl(gopts->uffd, UFFDIO_ZEROPAGE, uffdio_zeropage)) {
    	if (uffdio_zeropage->zeropage != -EEXIST)
    		err("UFFDIO_ZEROPAGE error: %"PRId64,
    		    (int64_t)uffdio_zeropage->zeropage);
@@ -903,16 +885,16 @@ static void retry_uffdio_zeropage(int ufd,
    }
 }
-static bool do_uffdio_zeropage(int ufd, bool has_zeropage)
+static bool do_uffdio_zeropage(uffd_global_test_opts_t *gopts, bool has_zeropage)
 {
    struct uffdio_zeropage uffdio_zeropage = { 0 };
    int ret;
    __s64 res;
-	uffdio_zeropage.range.start = (unsigned long) area_dst;
-	uffdio_zeropage.range.len = page_size;
+	uffdio_zeropage.range.start = (unsigned long) gopts->area_dst;
+	uffdio_zeropage.range.len = gopts->page_size;
    uffdio_zeropage.mode = 0;
-	ret = ioctl(ufd, UFFDIO_ZEROPAGE, &uffdio_zeropage);
+	ret = ioctl(gopts->uffd, UFFDIO_ZEROPAGE, &uffdio_zeropage);
    res = uffdio_zeropage.zeropage;
    if (ret) {
    	/* real retval in ufdio_zeropage.zeropage */
@@ -921,10 +903,10 @@ static bool do_uffdio_zeropage(int ufd, bool has_zeropage)
    	else if (res != -EINVAL)
    		err("UFFDIO_ZEROPAGE not -EINVAL");
    } else if (has_zeropage) {
-		if (res != page_size)
+		if (res != gopts->page_size)
    		err("UFFDIO_ZEROPAGE unexpected size");
    	else
-			retry_uffdio_zeropage(ufd, &uffdio_zeropage);
+			retry_uffdio_zeropage(gopts, &uffdio_zeropage);
    	return true;
    } else
    	err("UFFDIO_ZEROPAGE succeeded");
@@ -950,25 +932,29 @@ uffd_register_detect_zeropage(int uffd, void *addr, uint64_t len)
 }
/* exercise UFFDIO_ZEROPAGE */
-static void uffd_zeropage_test(uffd_test_args_t __unused *args)
+static void uffd_zeropage_test(uffd_global_test_opts_t *gopts, uffd_test_args_t __unused *args)
 {
    bool has_zeropage;
    int i;
-	has_zeropage = uffd_register_detect_zeropage(uffd, area_dst, page_size);
-	if (area_dst_alias)
+	has_zeropage = uffd_register_detect_zeropage(gopts->uffd,
+						     gopts->area_dst,
+						     gopts->page_size);
+	if (gopts->area_dst_alias)
    	/* Ignore the retval; we already have it */
-		uffd_register_detect_zeropage(uffd, area_dst_alias, page_size);
+		uffd_register_detect_zeropage(gopts->uffd, gopts->area_dst_alias, gopts->page_size);
-	if (do_uffdio_zeropage(uffd, has_zeropage))
-		for (i = 0; i < page_size; i++)
-			if (area_dst[i] != 0)
+	if (do_uffdio_zeropage(gopts, has_zeropage))
+		for (i = 0; i < gopts->page_size; i++)
+			if (gopts->area_dst[i] != 0)
    			err("data non-zero at offset %d\n", i);
-	if (uffd_unregister(uffd, area_dst, page_size))
+	if (uffd_unregister(gopts->uffd, gopts->area_dst, gopts->page_size))
    	err("unregister");
-	if (area_dst_alias && uffd_unregister(uffd, area_dst_alias, page_size))
+	if (gopts->area_dst_alias && uffd_unregister(gopts->uffd,
+						     gopts->area_dst_alias,
+						     gopts->page_size))
    	err("unregister");
uffd_test_pass();
@@ -987,26 +973,27 @@ static void uffd_register_poison(int uffd, void *addr, uint64_t len)
    	err("registered area doesn't support COPY and POISON ioctls");
 }
-static void do_uffdio_poison(int uffd, unsigned long offset)
+static void do_uffdio_poison(uffd_global_test_opts_t *gopts, unsigned long offset)
 {
    struct uffdio_poison uffdio_poison = { 0 };
    int ret;
    __s64 res;
-	uffdio_poison.range.start = (unsigned long) area_dst + offset;
-	uffdio_poison.range.len = page_size;
+	uffdio_poison.range.start = (unsigned long) gopts->area_dst + offset;
+	uffdio_poison.range.len = gopts->page_size;
    uffdio_poison.mode = 0;
-	ret = ioctl(uffd, UFFDIO_POISON, &uffdio_poison);
+	ret = ioctl(gopts->uffd, UFFDIO_POISON, &uffdio_poison);
    res = uffdio_poison.updated;
if (ret)
    	err("UFFDIO_POISON error: %"PRId64, (int64_t)res);
-	else if (res != page_size)
+	else if (res != gopts->page_size)
    	err("UFFDIO_POISON unexpected size: %"PRId64, (int64_t)res);
 }
-static void uffd_poison_handle_fault(
-	struct uffd_msg *msg, struct uffd_args __unused *args)
+static void uffd_poison_handle_fault(uffd_global_test_opts_t *gopts,
+				     struct uffd_msg *msg,
+				     struct uffd_args __unused *args)
 {
    unsigned long offset;
@@ -1017,20 +1004,20 @@ static void uffd_poison_handle_fault(
        (UFFD_PAGEFAULT_FLAG_WP | UFFD_PAGEFAULT_FLAG_MINOR))
    	err("unexpected fault type %llu", msg->arg.pagefault.flags);
-	offset = (char *)(unsigned long)msg->arg.pagefault.address - area_dst;
-	offset &= ~(page_size-1);
+	offset = (char *)(unsigned long)msg->arg.pagefault.address - gopts->area_dst;
+	offset &= ~(gopts->page_size-1);
/* Odd pages -> copy zeroed page; even pages -> poison. */
-	if (offset & page_size)
-		copy_page(uffd, offset, false);
+	if (offset & gopts->page_size)
+		copy_page(gopts, offset, false);
    else
-		do_uffdio_poison(uffd, offset);
+		do_uffdio_poison(gopts, offset);
 }
/* Make sure to cover odd/even, and minimum duplications */
 #define  UFFD_POISON_TEST_NPAGES  4
-static void uffd_poison_test(uffd_test_args_t __unused *targs)
+static void uffd_poison_test(uffd_global_test_opts_t *gopts, uffd_test_args_t __unused *targs)
 {
    pthread_t uffd_mon;
    char c;
@@ -1039,15 +1026,17 @@ static void uffd_poison_test(uffd_test_args_t __unused *targs)
    unsigned long nr_sigbus = 0;
    unsigned long nr, poison_pages = UFFD_POISON_TEST_NPAGES;
-	if (nr_pages < poison_pages) {
-		uffd_test_skip("Too few pages for POISON test");
+	if (gopts->nr_pages < poison_pages) {
+		uffd_test_skip("Too less pages for POISON test");
    	return;
    }
-	fcntl(uffd, F_SETFL, uffd_flags | O_NONBLOCK);
+	args.gopts = gopts;
+
+	fcntl(gopts->uffd, F_SETFL, gopts->uffd_flags | O_NONBLOCK);
-	uffd_register_poison(uffd, area_dst, poison_pages * page_size);
-	memset(area_src, 0, poison_pages * page_size);
+	uffd_register_poison(gopts->uffd, gopts->area_dst, poison_pages * gopts->page_size);
+	memset(gopts->area_src, 0, poison_pages * gopts->page_size);
args.handle_fault = uffd_poison_handle_fault;
    if (pthread_create(&uffd_mon, NULL, uffd_poll_thread, &args))
@@ -1060,8 +1049,8 @@ static void uffd_poison_test(uffd_test_args_t __unused *targs)
    	err("sigaction");
for (nr = 0; nr < poison_pages; ++nr) {
-		unsigned long offset = nr * page_size;
-		const char *bytes = (const char *) area_dst + offset;
+		unsigned long offset = nr * gopts->page_size;
+		const char *bytes = (const char *) gopts->area_dst + offset;
    	const char *i;
if (sigsetjmp(*sigbuf, 1)) {
@@ -1074,14 +1063,14 @@ static void uffd_poison_test(uffd_test_args_t __unused *targs)
    		continue;
    	}
-		for (i = bytes; i < bytes + page_size; ++i) {
+		for (i = bytes; i < bytes + gopts->page_size; ++i) {
    		if (*i)
    			err("nonzero byte in area_dst (%p) at %p: %u",
-				    area_dst, i, *i);
+				    gopts->area_dst, i, *i);
    	}
    }
-	if (write(pipefd[1], &c, sizeof(c)) != sizeof(c))
+	if (write(gopts->pipefd[1], &c, sizeof(c)) != sizeof(c))
    	err("pipe write");
    if (pthread_join(uffd_mon, NULL))
    	err("pthread_join()");
@@ -1094,7 +1083,9 @@ static void uffd_poison_test(uffd_test_args_t __unused *targs)
 }
static void
-uffd_move_handle_fault_common(struct uffd_msg *msg, struct uffd_args *args,
+uffd_move_handle_fault_common(uffd_global_test_opts_t *gopts,
+			      struct uffd_msg *msg,
+			      struct uffd_args *args,
    		      unsigned long len)
 {
    unsigned long offset;
@@ -1106,28 +1097,32 @@ uffd_move_handle_fault_common(struct uffd_msg *msg, struct uffd_args *args,
        (UFFD_PAGEFAULT_FLAG_WP | UFFD_PAGEFAULT_FLAG_MINOR | UFFD_PAGEFAULT_FLAG_WRITE))
    	err("unexpected fault type %llu", msg->arg.pagefault.flags);
-	offset = (char *)(unsigned long)msg->arg.pagefault.address - area_dst;
+	offset = (char *)(unsigned long)msg->arg.pagefault.address - gopts->area_dst;
    offset &= ~(len-1);
-	if (move_page(uffd, offset, len))
+	if (move_page(gopts, offset, len))
    	args->missing_faults++;
 }
-static void uffd_move_handle_fault(struct uffd_msg *msg,
+static void uffd_move_handle_fault(uffd_global_test_opts_t *gopts, struct uffd_msg *msg,
    			   struct uffd_args *args)
 {
-	uffd_move_handle_fault_common(msg, args, page_size);
+	uffd_move_handle_fault_common(gopts, msg, args, gopts->page_size);
 }
-static void uffd_move_pmd_handle_fault(struct uffd_msg *msg,
+static void uffd_move_pmd_handle_fault(uffd_global_test_opts_t *gopts, struct uffd_msg *msg,
    			       struct uffd_args *args)
 {
-	uffd_move_handle_fault_common(msg, args, read_pmd_pagesize());
+	uffd_move_handle_fault_common(gopts, msg, args, read_pmd_pagesize());
 }
static void
-uffd_move_test_common(uffd_test_args_t __unused *targs, unsigned long chunk_size,
-		      void (*handle_fault)(struct uffd_msg *msg, struct uffd_args *args))
+uffd_move_test_common(uffd_global_test_opts_t *gopts,
+		      uffd_test_args_t __unused *targs,
+		      unsigned long chunk_size,
+		      void (*handle_fault)(struct uffd_global_test_opts *gopts,
+		      struct uffd_msg *msg, struct uffd_args *args)
+)
 {
    unsigned long nr;
    pthread_t uffd_mon;
@@ -1139,11 +1134,13 @@ uffd_move_test_common(uffd_test_args_t __unused *targs, unsigned long chunk_size
    unsigned long src_offs = 0;
    unsigned long dst_offs = 0;
+	args.gopts = gopts;
+
    /* Prevent source pages from being mapped more than once */
-	if (madvise(area_src, nr_pages * page_size, MADV_DONTFORK))
+	if (madvise(gopts->area_src, gopts->nr_pages * gopts->page_size, MADV_DONTFORK))
    	err("madvise(MADV_DONTFORK) failure");
-	if (uffd_register(uffd, area_dst, nr_pages * page_size,
+	if (uffd_register(gopts->uffd, gopts->area_dst, gopts->nr_pages * gopts->page_size,
    		  true, false, false))
    	err("register failure");
@@ -1151,22 +1148,22 @@ uffd_move_test_common(uffd_test_args_t __unused *targs, unsigned long chunk_size
    if (pthread_create(&uffd_mon, NULL, uffd_poll_thread, &args))
    	err("uffd_poll_thread create");
-	step_size = chunk_size / page_size;
-	step_count = nr_pages / step_size;
+	step_size = chunk_size / gopts->page_size;
+	step_count = gopts->nr_pages / step_size;
-	if (chunk_size > page_size) {
-		char *aligned_src = ALIGN_UP(area_src, chunk_size);
-		char *aligned_dst = ALIGN_UP(area_dst, chunk_size);
+	if (chunk_size > gopts->page_size) {
+		char *aligned_src = ALIGN_UP(gopts->area_src, chunk_size);
+		char *aligned_dst = ALIGN_UP(gopts->area_dst, chunk_size);
-		if (aligned_src != area_src || aligned_dst != area_dst) {
-			src_offs = (aligned_src - area_src) / page_size;
-			dst_offs = (aligned_dst - area_dst) / page_size;
+		if (aligned_src != gopts->area_src || aligned_dst != gopts->area_dst) {
+			src_offs = (aligned_src - gopts->area_src) / gopts->page_size;
+			dst_offs = (aligned_dst - gopts->area_dst) / gopts->page_size;
    		step_count--;
    	}
-		orig_area_src = area_src;
-		orig_area_dst = area_dst;
-		area_src = aligned_src;
-		area_dst = aligned_dst;
+		orig_area_src = gopts->area_src;
+		orig_area_dst = gopts->area_dst;
+		gopts->area_src = aligned_src;
+		gopts->area_dst = aligned_dst;
    }
/*
@@ -1180,34 +1177,34 @@ uffd_move_test_common(uffd_test_args_t __unused *targs, unsigned long chunk_size
/* Check area_src content */
    	for (i = 0; i < step_size; i++) {
-			count = *area_count(area_src, nr + i);
-			if (count != count_verify[src_offs + nr + i])
+			count = *area_count(gopts->area_src, nr + i, gopts);
+			if (count != gopts->count_verify[src_offs + nr + i])
    			err("nr %lu source memory invalid %llu %llu\n",
-				    nr + i, count, count_verify[src_offs + nr + i]);
+				    nr + i, count, gopts->count_verify[src_offs + nr + i]);
    	}
/* Faulting into area_dst should move the page or the huge page */
    	for (i = 0; i < step_size; i++) {
-			count = *area_count(area_dst, nr + i);
-			if (count != count_verify[dst_offs + nr + i])
+			count = *area_count(gopts->area_dst, nr + i, gopts);
+			if (count != gopts->count_verify[dst_offs + nr + i])
    			err("nr %lu memory corruption %llu %llu\n",
-				    nr, count, count_verify[dst_offs + nr + i]);
+				    nr, count, gopts->count_verify[dst_offs + nr + i]);
    	}
/* Re-check area_src content which should be empty */
    	for (i = 0; i < step_size; i++) {
-			count = *area_count(area_src, nr + i);
+			count = *area_count(gopts->area_src, nr + i, gopts);
    		if (count != 0)
    			err("nr %lu move failed %llu %llu\n",
-				    nr, count, count_verify[src_offs + nr + i]);
+				    nr, count, gopts->count_verify[src_offs + nr + i]);
    	}
    }
-	if (chunk_size > page_size) {
-		area_src = orig_area_src;
-		area_dst = orig_area_dst;
+	if (chunk_size > gopts->page_size) {
+		gopts->area_src = orig_area_src;
+		gopts->area_dst = orig_area_dst;
    }
-	if (write(pipefd[1], &c, sizeof(c)) != sizeof(c))
+	if (write(gopts->pipefd[1], &c, sizeof(c)) != sizeof(c))
    	err("pipe write");
    if (pthread_join(uffd_mon, NULL))
    	err("join() failed");
@@ -1218,24 +1215,24 @@ uffd_move_test_common(uffd_test_args_t __unused *targs, unsigned long chunk_size
    	uffd_test_pass();
 }
-static void uffd_move_test(uffd_test_args_t *targs)
+static void uffd_move_test(uffd_global_test_opts_t *gopts, uffd_test_args_t *targs)
 {
-	uffd_move_test_common(targs, page_size, uffd_move_handle_fault);
+	uffd_move_test_common(gopts, targs, gopts->page_size, uffd_move_handle_fault);
 }
-static void uffd_move_pmd_test(uffd_test_args_t *targs)
+static void uffd_move_pmd_test(uffd_global_test_opts_t *gopts, uffd_test_args_t *targs)
 {
-	if (madvise(area_dst, nr_pages * page_size, MADV_HUGEPAGE))
+	if (madvise(gopts->area_dst, gopts->nr_pages * gopts->page_size, MADV_HUGEPAGE))
    	err("madvise(MADV_HUGEPAGE) failure");
-	uffd_move_test_common(targs, read_pmd_pagesize(),
+	uffd_move_test_common(gopts, targs, read_pmd_pagesize(),
    		      uffd_move_pmd_handle_fault);
 }
-static void uffd_move_pmd_split_test(uffd_test_args_t *targs)
+static void uffd_move_pmd_split_test(uffd_global_test_opts_t *gopts, uffd_test_args_t *targs)
 {
-	if (madvise(area_dst, nr_pages * page_size, MADV_NOHUGEPAGE))
+	if (madvise(gopts->area_dst, gopts->nr_pages * gopts->page_size, MADV_NOHUGEPAGE))
    	err("madvise(MADV_NOHUGEPAGE) failure");
-	uffd_move_test_common(targs, read_pmd_pagesize(),
+	uffd_move_test_common(gopts, targs, read_pmd_pagesize(),
    		      uffd_move_pmd_handle_fault);
 }
@@ -1295,6 +1292,11 @@ typedef enum {
    THR_STATE_UNINTERRUPTIBLE,
 } thread_state;
+typedef struct {
+	uffd_global_test_opts_t *gopts;
+	volatile pid_t *pid;
+} mmap_changing_thread_args;
+
 static void sleep_short(void)
 {
    usleep(1000);
@@ -1337,7 +1339,9 @@ static void thread_state_until(pid_t tid, thread_state state)
static void *uffd_mmap_changing_thread(void *opaque)
 {
-	volatile pid_t *pid = opaque;
+	mmap_changing_thread_args *args = opaque;
+	uffd_global_test_opts_t *gopts = args->gopts;
+	volatile pid_t *pid = args->pid;
    int ret;
/* Unfortunately, it's only fetch-able from the thread itself.. */
@@ -1345,21 +1349,22 @@ static void *uffd_mmap_changing_thread(void *opaque)
    *pid = syscall(SYS_gettid);
/* Inject an event, this will hang solid until the event read */
-	ret = madvise(area_dst, page_size, MADV_REMOVE);
+	ret = madvise(gopts->area_dst, gopts->page_size, MADV_REMOVE);
    if (ret)
    	err("madvise(MADV_REMOVE) failed");
return NULL;
 }
-static void uffd_consume_message(void)
+static void uffd_consume_message(uffd_global_test_opts_t *gopts)
 {
    struct uffd_msg msg = { 0 };
-	while (uffd_read_msg(&msg));
+	while (uffd_read_msg(gopts, &msg));
 }
-static void uffd_mmap_changing_test(uffd_test_args_t __unused *targs)
+static void uffd_mmap_changing_test(uffd_global_test_opts_t *gopts,
+				    uffd_test_args_t __unused *targs)
 {
    /*
     * This stores the real PID (which can be different from how tid is
@@ -1368,13 +1373,14 @@ static void uffd_mmap_changing_test(uffd_test_args_t __unused *targs)
    pid_t pid = 0;
    pthread_t tid;
    int ret;
+	mmap_changing_thread_args args = { gopts, &pid };
-	if (uffd_register(uffd, area_dst, nr_pages * page_size,
+	if (uffd_register(gopts->uffd, gopts->area_dst, gopts->nr_pages * gopts->page_size,
    		  true, false, false))
    	err("uffd_register() failed");
/* Create a thread to generate the racy event */
-	ret = pthread_create(&tid, NULL, uffd_mmap_changing_thread, &pid);
+	ret = pthread_create(&tid, NULL, uffd_mmap_changing_thread, &args);
    if (ret)
    	err("pthread_create() failed");
@@ -1388,26 +1394,26 @@ static void uffd_mmap_changing_test(uffd_test_args_t __unused *targs)
    /* Wait until the thread hangs at REMOVE event */
    thread_state_until(pid, THR_STATE_UNINTERRUPTIBLE);
-	if (!uffdio_mmap_changing_test_copy(uffd))
+	if (!uffdio_mmap_changing_test_copy(gopts->uffd))
    	return;
-	if (!uffdio_mmap_changing_test_zeropage(uffd))
+	if (!uffdio_mmap_changing_test_zeropage(gopts->uffd))
    	return;
-	if (!uffdio_mmap_changing_test_move(uffd))
+	if (!uffdio_mmap_changing_test_move(gopts->uffd))
    	return;
-	if (!uffdio_mmap_changing_test_poison(uffd))
+	if (!uffdio_mmap_changing_test_poison(gopts->uffd))
    	return;
-	if (!uffdio_mmap_changing_test_continue(uffd))
+	if (!uffdio_mmap_changing_test_continue(gopts->uffd))
    	return;
/*
     * All succeeded above!  Recycle everything.  Start by reading the
     * event so as to kick the thread roll again..
     */
-	uffd_consume_message();
+	uffd_consume_message(gopts);
ret = pthread_join(tid, NULL);
    assert(ret == 0);
@@ -1415,10 +1421,10 @@ static void uffd_mmap_changing_test(uffd_test_args_t __unused *targs)
    uffd_test_pass();
 }
-static int prevent_hugepages(const char **errmsg)
+static int prevent_hugepages(uffd_global_test_opts_t *gopts, const char **errmsg)
 {
    /* This should be done before source area is populated */
-	if (madvise(area_src, nr_pages * page_size, MADV_NOHUGEPAGE)) {
+	if (madvise(gopts->area_src, gopts->nr_pages * gopts->page_size, MADV_NOHUGEPAGE)) {
    	/* Ignore only if CONFIG_TRANSPARENT_HUGEPAGE=n */
    	if (errno != EINVAL) {
    		if (errmsg)
@@ -1429,10 +1435,10 @@ static int prevent_hugepages(const char **errmsg)
    return 0;
 }
-static int request_hugepages(const char **errmsg)
+static int request_hugepages(uffd_global_test_opts_t *gopts, const char **errmsg)
 {
    /* This should be done before source area is populated */
-	if (madvise(area_src, nr_pages * page_size, MADV_HUGEPAGE)) {
+	if (madvise(gopts->area_src, gopts->nr_pages * gopts->page_size, MADV_HUGEPAGE)) {
    	if (errmsg) {
    		*errmsg = (errno == EINVAL) ?
    			"CONFIG_TRANSPARENT_HUGEPAGE is not set" :
@@ -1456,13 +1462,17 @@ struct uffd_test_case_ops uffd_move_test_pmd_case_ops = {
  * Note that _UFFDIO_ZEROPAGE is tested separately in the zeropage test.
  */
 static void
-do_register_ioctls_test(uffd_test_args_t *args, bool miss, bool wp, bool minor)
+do_register_ioctls_test(uffd_global_test_opts_t *gopts,
+			uffd_test_args_t *args,
+			bool miss,
+			bool wp,
+			bool minor)
 {
    uint64_t ioctls = 0, expected = BIT_ULL(_UFFDIO_WAKE);
    mem_type_t *mem_type = args->mem_type;
    int ret;
-	ret = uffd_register_with_ioctls(uffd, area_dst, page_size,
+	ret = uffd_register_with_ioctls(gopts->uffd, gopts->area_dst, gopts->page_size,
    				miss, wp, minor, &ioctls);
/*
@@ -1493,18 +1503,18 @@ do_register_ioctls_test(uffd_test_args_t *args, bool miss, bool wp, bool minor)
    	    "(miss=%d, wp=%d, minor=%d): expected=0x%"PRIx64", "
    	    "returned=0x%"PRIx64, miss, wp, minor, expected, ioctls);
-	if (uffd_unregister(uffd, area_dst, page_size))
+	if (uffd_unregister(gopts->uffd, gopts->area_dst, gopts->page_size))
    	err("unregister");
 }
-static void uffd_register_ioctls_test(uffd_test_args_t *args)
+static void uffd_register_ioctls_test(uffd_global_test_opts_t *gopts, uffd_test_args_t *args)
 {
    int miss, wp, minor;
for (miss = 0; miss <= 1; miss++)
    	for (wp = 0; wp <= 1; wp++)
    		for (minor = 0; minor <= 1; minor++)
-				do_register_ioctls_test(args, miss, wp, minor);
+				do_register_ioctls_test(gopts, args, miss, wp, minor);
uffd_test_pass();
 }
@@ -1742,6 +1752,28 @@ int main(int argc, char *argv[])
    	}
    	for (j = 0; j < n_mems; j++) {
    		mem_type = &mem_types[j];
+
+			/* Initialize global test options */
+			uffd_global_test_opts_t gopts = { 0 };
+
+			gopts.map_shared = mem_type->shared;
+			uffd_test_ops = mem_type->mem_ops;
+			uffd_test_case_ops = test->test_case_ops;
+
+			if (mem_type->mem_flag & (MEM_HUGETLB_PRIVATE | MEM_HUGETLB))
+				gopts.page_size = default_huge_page_size();
+			else
+				gopts.page_size = psize();
+
+			/* Ensure we have at least 2 pages */
+			gopts.nr_pages = MAX(UFFD_TEST_MEM_SIZE, gopts.page_size * 2)
+				/ gopts.page_size;
+
+			gopts.nr_parallel = 1;
+
+			/* Initialize test arguments */
+			args.mem_type = mem_type;
+
    		if (!(test->mem_targets & mem_type->mem_flag))
    			continue;
@@ -1756,13 +1788,12 @@ int main(int argc, char *argv[])
    			uffd_test_skip("feature missing");
    			continue;
    		}
-			if (uffd_setup_environment(&args, test, mem_type,
-						   &errmsg)) {
+			if (uffd_test_ctx_init(&gopts, test->uffd_feature_required, &errmsg)) {
    			uffd_test_skip(errmsg);
    			continue;
    		}
-			test->uffd_fn(&args);
-			uffd_test_ctx_clear();
+			test->uffd_fn(&gopts, &args);
+			uffd_test_ctx_clear(&gopts);
    	}
    }
diff --git a/tools/testing/selftests/mm/uffd-wp-mremap.c b/tools/testing/selftests/mm/uffd-wp-mremap.c
index b2b6116e6580..ec860625b25b 100644
--- a/tools/testing/selftests/mm/uffd-wp-mremap.c
+++ b/tools/testing/selftests/mm/uffd-wp-mremap.c
@@ -152,7 +152,11 @@ static bool range_is_swapped(void *addr, size_t size)
    return true;
 }
-static void test_one_folio(size_t size, bool private, bool swapout, bool hugetlb)
+static void test_one_folio(uffd_global_test_opts_t *gopts,
+			   size_t size,
+			   bool private,
+			   bool swapout,
+			   bool hugetlb)
 {
    struct uffdio_writeprotect wp_prms;
    uint64_t features = 0;
@@ -176,21 +180,21 @@ static void test_one_folio(size_t size, bool private, bool swapout, bool hugetlb
    }
/* Register range for uffd-wp. */
-	if (userfaultfd_open(&features)) {
+	if (userfaultfd_open(gopts, &features)) {
    	if (errno == ENOENT)
    		ksft_test_result_skip("userfaultfd not available\n");
    	else
    		ksft_test_result_fail("userfaultfd_open() failed\n");
    	goto out;
    }
-	if (uffd_register(uffd, mem, size, false, true, false)) {
+	if (uffd_register(gopts->uffd, mem, size, false, true, false)) {
    	ksft_test_result_fail("uffd_register() failed\n");
    	goto out;
    }
    wp_prms.mode = UFFDIO_WRITEPROTECT_MODE_WP;
    wp_prms.range.start = (uintptr_t)mem;
    wp_prms.range.len = size;
-	if (ioctl(uffd, UFFDIO_WRITEPROTECT, &wp_prms)) {
+	if (ioctl(gopts->uffd, UFFDIO_WRITEPROTECT, &wp_prms)) {
    	ksft_test_result_fail("ioctl(UFFDIO_WRITEPROTECT) failed\n");
    	goto out;
    }
@@ -237,9 +241,9 @@ static void test_one_folio(size_t size, bool private, bool swapout, bool hugetlb
 out:
    if (mem)
    	munmap(mem, size);
-	if (uffd >= 0) {
-		close(uffd);
-		uffd = -1;
+	if (gopts->uffd >= 0) {
+		close(gopts->uffd);
+		gopts->uffd = -1;
    }
 }
@@ -331,6 +335,7 @@ static const struct testcase testcases[] = {
int main(void)
 {
+	uffd_global_test_opts_t gopts = { 0 };
    struct thp_settings settings;
    int i, j, plan = 0;
@@ -362,8 +367,8 @@ int main(void)
    	const struct testcase *tc = &testcases[i];
for (j = 0; j < *tc->nr_sizes; j++)
-			test_one_folio(tc->sizes[j], tc->private, tc->swapout,
-				       tc->hugetlb);
+			test_one_folio(&gopts, tc->sizes[j], tc->private,
+				       tc->swapout, tc->hugetlb);
    }
/* If THP is supported, restore original THP settings. */
-- 
2.30.2



    